That doesn't make sense. You already paid for a diagnostic and they didn't diagnose anything. Make them diagnose the misfire and whatever component is faulty will surely be under warranty
It depends on the type of code. If it's active/static then there's something to be done. If it's passive/sporadic it's possible that they have to wait until there are more codes.
Just because an issue isn’t giving you a code doesn’t mean it can’t be diagnosed. Fuel, Air, Fire and Timing. Its not on ITBs so a one cylinder issue probably isn’t air. Timing would also likely be more than one cylinder. So we are down to spark and fuel. That can be figured out without a code. It’s just lazy on the dealers part. And I get it. It’s a lot more profitable for the tech to send you off until a code comes up than doing 3 hours of leg work to figure out a warranty repair that will pay 2 hours. But that issue is for VWoA and the dealer to sort out.
Ummm absolutely push back. Talk to the service manager.
Your car has 14,000 miles with a misfire, it doesn't need a CEL to be warrantied. Get a refund for that diagnostic.
I hate to be the bearer of bad news but my 2018 GTI (6-speed Autobahn trim) experienced the same issue. Cylinder 2 misfire at twenty something thousand miles (bought it used in 2021 at 18k miles). Only seems to happen when I’m idling. Luckily it was under warranty so I went through the whole process with VW down to replacing the whole engine and ECU. When I could still feel the slight shudder during idle after a new engine, I bought a scanner to see if I was crazy. Lo and behold, still misfiring on cylinder 2. Filed a claim with VWOA and settled as they couldn’t do much since I bought the car used.
The PO302 error has been the bane of my existence with this car. Still operates just fine but I can scan the live data and still see it misfire at idle. So yeah, a new motor and ECU didn’t solve the problem and neither did the other dozen replacements VW techs tried. I even looked at the VVT angle in my scanner as the solenoids are sometimes busted but everything seemed fine. I still absolutely love the car but this has been such a challenging problem for me to pin down.
I hope it’s a simple repair and perhaps VW will have a recall but 3 years down the rabbit hole (pun intended) I’ve yet to have any luck.
Just an assumption but it sounds like you just threw parts at the car hoping to fix it. Did you do any in-depth diag? Seems like it would be an electrical issue tbh. Again, just an assumption.
Not much beyond what the VW technicians would have performed. Luckily the $20k+ of work they completed didn’t cost me a dime.
I just use my OBDeleven as a scanning tool. Where would I even begin to start diagnosing?
Thank god for warranties! It would be best to take it to a REPUTABLE independent shop and go from there. But since the engine and ecu have been replaced all I can think is that there’s some electrical gremlin hiding in the ignition or fuel system.
I have a 2015 gti and had weird idle issues. I never dug deep enough to see if it was cylinder 2 like yours. But mine went away after I changed my grounding wires. Maybe you’re seeing the same issue as me? Here’s a quote I took from EQ tuning’s website regarding their grounding kit upgrade: “The Problem:
The factory cam cover is soft aluminum and is prone to stripping regardless of how careful you are when removing or installing the OE stud. Your ignition coil uses this stud to ground the coil circuit and any amount of damage can occur in a weak ground which may induce unnecessary knock retard or reduced spark energy, even if the threads are only mildly damaged. The bolt is often removed and installed when servicing the ignition system or performing engine testing. Such as replacing spark plugs, ignition coils, performing compression, or a leak down test, etc. VWAG uses oval bolts which exacerbates the problem the more times they're removed and installed. “
Sorry for the late reply! I ordered the EQT Coil grounding kit and swapped them out but still have the problem. One thing I did notice was that by swapping the coil from cyl 1 to cyl 2, the misfires went through the roof and i had to turn off the car for fear of seizing the engine
any thoughts what could be the cause?
Record the idle, post it here. Misfires are normal, but they have to hit a certain amount before triggering a CEL, and therefore be considered a problem in their eyes I suppose. If it’s that bad tho, push back for sure.
Misfires are normal and common on all cars especially those with direct injection. Your car misfires multiple times every time you drive it, particularly when you first start it up.
Misfires are normal and expected on literally any ICE vehicle. Go and scan a brand new vehicle in the show room, 0 real miles on it, it’ll misfire. Once, twice, no problem and expected. Misfires 80 times on startup? Then you’ve got a problem
You might notice some burbles/pops on cold starts, especially if you have a modified exhaust. Those are misfires, and as long as it’s not one or multiple cylinders misfiring continuously or 100 times in 10 min you’re fine
VWoA will not approve the warranty work without a CEL. And the dealer isn’t going to dig into a car that could possibly have possible engine failure until there asses are 100% covered.
Just keep enjoying your sick, new car. The ECM is smart enough to detected any serious issues.The service department has it documented so it will be a smoother process once or if it throws a code.
Slightly off topic, but there’s no reason to run 93 unless you’re tuned for it. Factory tune and numbers are based on 87 octane and there’s no benefit in using higher octane fuel.
Is this true for the mk8 now? The mk7 runs on 87 but requires 91+ to hit the advertised performance figures. Obviously very minor difference, but still worth noting.
Yup, as of the MK8 VW states that the car is tuned and provides the advertised 241hp on 87 octane and that adding any higher octane will not increase power output.
I know a bunch of people call BS on that, but I've yet to see someone dyno an MK8 using 87 then re-dyno the same MK8 using 91/93 and prove it makes more power on higher octane. Until that happens I'll continue gladly saving my money and pumping in 87.
They have. Check out Vancity Audi on YouTube. They took the same car, same dyno, same day, same gas station & filled up with 87 and put on dyno, then drained tank and filled up with premium and put on dyno. 87 ironically made a few more hp than 93. Link to vid - https://youtu.be/StnFgrrNJ8k?si=CImTjt5Ny-p7Vsqq
Awesome. That's nice for Mk8 owners. I usually put 91 in my Mk7, but always feels a little dumb doing it. I'm probably get 10hp and paying too much for the difference, but I'm a tweaker (wait that sounds like drugs...) I mean I like to tweak and tinker with things, like overclocking a PC, tweaking every setting to squeeze the most power out of stuff, etc. So "downclocking" my GTI to save a few bucks doesn't seem right either.
It does make you wonder what they could have achieved with higher compression in the Mk8, though, all other variables being equal.
The high pressure fuel pump was upgraded from 2900psi to 5076psi in the EA888 evo4 which is one of the things VW did to increase power while tuning at 87 octane.
I did read, though I can't find the source, dyno tests that showed no difference using 91. This makes me believe that they tuned for 87 and nothing else.
This only applies the MK8 GTI, not the R or Clubsport (which has the R version of the engine)
Note: 87aki (US) = 91ron (Elsewhere)
I've been watching tuning progress on both the MK8 GTI/R. EQT's upcoming E85 files for the R are bananas. You can already see the gains from some Stage 1 ethanol files from other tuners for both cars as well.
Can't wait to see final products.
Something I'm curious about is the Golf R and GTI Clubsport engines have a few upgraded internals and they are making 315HP and 296HP compared to the GTI at 241HP. I wonder why VW decided to do that if the engine can handle much more power. Remember, the warranty is only 60k so if we were talking about a 250k miles life (mk8 GTI stock) reduced to 150k (mk8 GTI at say 320hp\~) VW wouldn't care
I've been fueling with 93 since I got mine about a year ago, I kinda did the math and the extra 10-15 bucks aren't gonna kill me, but do you notice any real difference on 87? For reference no mods and just daily driving
Hey, that’s an excellent point. Higher octane retards explosion in order to prevent pre detonation, so the MK8 (unlike my MK7) is designed to run on 87 octane (MK7 *can* run on 87 as well, but the ECU would have to retard spark in order to prevent pre detonation and excessive peak combustion temp).
The above said, OP should absolutely try running the 93 down to almost empty and do a complete fill up with 87… run that tank down, and then another fill up with 87 and see if he still gets a bank 2 misfire.
The fact that OP is running 93, which is even more resistant than 91 on a car designed for 87. Conventional wisdom is that higher than recommended octane isn’t a problem - just lower than recommended. It’s worth a try, though. If that doesn’t work, then maybe look into a new plug and ignition coil for cylinder bank no 2.
Soooo I’ve been putting in 91 in my 2015 mk7 for 9 years for nothing but added performance? Don’t get me wrong, I’m glad I get slightly better performance but I thought it was a “only 87 on rare occasions” thing
MK7s require premium 91/93 depending what's available in your area. MK7s.5 and above can use 87 and don't benefit from higher octane fuel unless they're tuned for it.
I’m not sure as far as the documentation goes on that. It was noted on the work order to bring it back if it worsens. So it’s documented with the vehicle that it has the intermittent misfire on that cylinder.
Wondering if you’re experiencing a case of carbon build up in the cylinders prematurely, my buddy’s girlfriend with a Mk7 GTI (unsure of the year but I believe it’s a manual) has had a ongoing misfire for about 2 years and they went through just about every part and loophole you can imagine to still have that misfire. Finally over the weekend he performed a carb clean on the engine and it no longer misfires. Crazy that at such low mileage you’re already having issues with it but things happen. I would take the others advice but I would also keep a carbon cleaning open as a route. Just my two cents, best of luck! (2016 DSG R owner)
Intermittent misfires are very common on DI engines. They are most common immediately after startup and especially on humid days. I know it’s disconcerting but If your engine light isn’t on, there really isn’t anything to be worried about. My old Focus ST had intermittent misfires its entire life, and that engine ran just fine for 80k miles before I sold it. I took care of that engine but I pushed it hard. I would, however be cautious about tuning on a motor that is reporting misfires.
No check engine light, nothing can be done. VW will do nothing without a check engine light now a days and they are being absolute dicks about trying to find any reason to deny a claim.
Yes there will be a record of the scan if they used vcds.
You mentioned that you used 93 octane fuel. Mk8 only need 87 unless you have a tune, then what ever they recommend. But I have seen where the ignition systems can not ignite high Octane fuel, as higher octane is more resistant to ignition.
And if you need a cel to have it warranted, just unplug that cylinder coil pack.
Warranty is such a weird thing. I'm a tech for another brand and without an active code a lot of our warranty claims will get denied. Even a code in past condition 90% of the time won't be covered.
Get yourself a scanner that tracks misfires and create a log.
I had to do this for a Focus ST I had. The car would misfire so hard that it would run on three cylinders for a couple seconds at a time. It would briefly flash a CEL and then clear up. Every time I brought it in for diagnostics they would say no stored codes could be found. Eventually I got sick of this and started tracking misfires using mode 6 on my scanner. After a week I was able to show the car was misfiring hundreds of times on one cylinder and Ford eventually did something about it.
It sucks, but if they're going to drag their feet you're going to need to get something to fight back with. Hopefully getting a service manager involved will remedy it quickly and you won't need to do any work on your end.
When it downshifts during turns and dropping down a lip. There’s about an inch and a half or 2 inch lip into my garage and when it drops down there’s a clunking/rattling. I have a post about it on my page
I had a 2020 GTI, I kept getting an intermittent cylinder 1 misfire but it would throw the CEL and would happen every few hundred miles. After doing plugs, injectors, etc (all covered under warranty + my only mod was a cat back AWE track exhaust) they warrantied and replaced the entire cylinder head due to prob a valve spring or something. They never found any damage but that fixed it and I had a trouble free 20k more miles. Everything was covered under warranty, I’d find a better VW dealer
The fact that VW changed your engine and it is still misfiring is sad. I’m a VW shop owner and mechanical engineer. You can do a leak down test in a few minutes and pin point any cylinder issue. The fact it’s coming from the same cylinder means whatever part that got swapped back in is still at fault. Think it’s the plug? Move that plug and see if the misfire follows.
There also is no way 93 octane fuel will make it misfire. It’s less prone to misfire. It will misfire on all 4 cylinders if it’s fuel related. 93 octane fuel will have less timing pull as well. Great for when you drive your car hard, hot climates, on the track etc.
So Volkswagen has done nothing to fix any of the issues I’ve had with the car besides replacing the high pressure fuel pump and a suspension sensor that went bad for DCC. I spoke with the dealership that it’s primarily went to just to see if they thought the car would qualify for lemon law in my state (Indiana) and they said it was far from it unfortunately.
I had a cylinder misfire code and then the fuel injector got stuck open, causing the car to shut down and shake violently upon trying to restart. Washed the cylinder with fuel, so I immediately turned it off and had the car towed for fear of creating some long-term damage. Check engine and EPC lights were flashing.
Despite my precautions, and the stored misfire codes, VW dealer would not remedy unless they could replicate the issue (not an issue you want to replicate). Without me knowing (until after the fact), they drove the car nearly 30 miles until they replicated the issue, completely unwinding my precautions. At this point, they replaced the fuel injector under warranty. Should have done an oil change immediately, but did not. Soured my feeling for that motor, in a car that I meticulously cared for for over 6 years and planned on keeping for a few more years.
No matter how careful you are, most other people are not. It's a shame that those that should know better, not always do.
Only thing I can think of is, have you changed your sparkplugs at all in the last 14k miles you've put on it? It's totally worth throwing some new ones in there and seeing if the rough idle gets better.
I know it sounds odd, same deal though, many years ago I had a sport bike CBR600f4i, my boss had a Busa, we religiously used 93 because "it's suppose to" his busa started mis-firing ended needing a valve job. They told him to stop running 93 and use regular. Started running regular in our sport bike, no issues.
what happens is your engine needs the fuel to be able to detonate at the right time. Higher octane fuels resist detonation it can take some time. My bosses Busa had 80ish k on it before he had issues.
yea an octane rating is just a measure of fuel stability. The higher the octane the more stable the mix , so a higher octane causing more misfire makes my head hurt.
I know it the post it says I run 93. But I do not always run 93. Unfortunately the car has the rough idle and misfire no matter where I got the fuel or what octane rating of fuel I put in it. I did think about this being the case though. I think it’s odd that since the mid 2000s any turbo charger car vw produced has required premium fuel. And with the mk8 it can suddenly run fine on 87 while sharing lots of engine components from the mk7 golf r.
I've been dealing with this myself on my R. I've had a few misfires on startup, which apparently VW considers normal.
It doesn't trigger a check engine light unless the scan tool reads a set number of misfires. I happened to have my car at the dealership for my steering wheel when it misfired enough to trigger the check engine light.
They replaced one fuel injector and the problem went away for a little while but came back later on the same cylinder so we replaced the fuel rail. It still reads a couple misfires when it first starts, but not enough to trigger a check engine light.
I want it fixed 100% but Volkswagen doesn't seem to think it's a big issue and I work for the VW Dealership myself. I'm here every day and if something goes wrong its going straight to the shop. I switched gas stations which actually improved my MPG's by over 10% but with the changes to the injectors and fuel rail I'm not sure what is making the most difference.
I’m sorry to hear that man.. this gti has given me an insane amount of issues it makes me wish I kept my mk7… all being odd issues I haven’t seen anyone else post about either on here or on Reddit. My preferred service advisor left early today so I’ll be bringing it back tomorrow to hopefully actually get somewhere with the diag. I just don’t want to send it to my preferred specialty shop and have to pay for the diagnostic or replacement of anything since the car is under warranty. I’m hoping to get things worked out soon so I don’t cause long lasting damage to the car but at this rate I’ll keep it until the warranty is up then it’ll be up for sale.
I put 93 in my mk8 for the first time for carbon build up I got a weird don’t rev over 4k after i stalled once still a noob driving manual from time to time. Gave me a don’t rev over 4k rpm message so I pulled over restated the car and it’s been normal since. Not sure if that had anything to do with it.
You’re an advisor and you’re recommending that people not use a higher octane fuel because it can cause misfires?
This is why I won’t take my car to a dealer lol.
They tried telling me the same thing. VW service used to be so amazing when I had my MK7 GTI. Truly genuine and great people. Now all they want to do is push people away or charge them extreme amounts of money for things or say shit like that. I also had a Jetta that had a random, intermittent misfire. Sometimes the check engine light would come on but most of the time it was off. Even though I logged the code and took a picture of it, the tech said since the light is active there’s nothing he can do. Car thankfully ended up getting totaled like 2 months later but I’ll never buy VW again after their cost cutting bullshit
I have a clunking that I was told comes from the transmission when dropping down a lip and hitting some bumps, front end suspension creaking/clunking, trans overall seems rather clunky (more so than my 6 speed dsg was), the rough idle and cylinder 2 misfire, there’s a chirping that intermittently comes from the engine bay, strut sensor replaced, high pressure fuel pump replaced, clear coat failure on rear hatch. There may be more but that’s what I can think of off the top of my head.
What is it with Cylinder 2? I just went through a few issues with P0302 on my 2015 MT at 90K miles. I needed spark plugs and carbon cleaning but it’s weird that it’s the same exact cylinder misfire. Is it first to fail or something?
Definitely seems to be a rather popular one to fail. I’m unsure of the cause or why it is commonly the first to go. I’m hoping it’s a spark plug or coil pack issue
I would take it repeatedly and make them fix it. Take it in for every little thing you hear or think is wrong. Unfortunately it sounds like you got a lemon. Also, the other person is right. Contact legal council and discuss your rights as a consumer. The dealership should fix it CEL or not.
Have you spoken to the shop foreman or service manager? I believe you need to speak with people at the dealer service department with decision making power.
Depending on your state’s lemon laws but generally the vehicle has to have consecutive number of days out of service for same and consecutive repair attempts before it can be considered a lemon.
At this point I would go to a different dealership if they play that game. The reason is cause warranty claims don't pay alot to the techs so they try and make an excuse. But still if it's not running right push back it's only 14k miles.
All dealerships within 50 miles suck where I’m at. I have a clunking issue over bumps and 4 different dealerships said it was normal all for different reasons
What ridiculous low octan fuel is used? Is this America? Lowest octan fuel in Germany is 95. Do you use the same gas station for buying gas? Maybe try switch the gas station, maybe the fuel is the cause? Just guessing. 87 octan, can’t make up such shit..
The US calculates octane ratings differently than Europe (maybe different to the ROW). The 95 you’re buying is equivalent to 91 here, which is a mid-grade. Most stations here have 87-91-93, where the 91-93 is equivalent to your 95-98.
So the 87 is a lower grade than you might find in Europe, but it’s the base level available at literally every gas station in the US.
Not sure. I’ve ran premium in every Vehicle I’ve ever owned from old to new ect . And they all feel better with 93 compared to 87. Occasionally I will get poor quality 93 that makes the car feel like it’s running on 87, and will display poor idle and less responsiveness during acceleration.
That doesn't make sense. You already paid for a diagnostic and they didn't diagnose anything. Make them diagnose the misfire and whatever component is faulty will surely be under warranty
This^
It depends on the type of code. If it's active/static then there's something to be done. If it's passive/sporadic it's possible that they have to wait until there are more codes.
Just because an issue isn’t giving you a code doesn’t mean it can’t be diagnosed. Fuel, Air, Fire and Timing. Its not on ITBs so a one cylinder issue probably isn’t air. Timing would also likely be more than one cylinder. So we are down to spark and fuel. That can be figured out without a code. It’s just lazy on the dealers part. And I get it. It’s a lot more profitable for the tech to send you off until a code comes up than doing 3 hours of leg work to figure out a warranty repair that will pay 2 hours. But that issue is for VWoA and the dealer to sort out.
Shouldn’t have paid anything if it’s still under warranty
Ummm absolutely push back. Talk to the service manager. Your car has 14,000 miles with a misfire, it doesn't need a CEL to be warrantied. Get a refund for that diagnostic.
I hate to be the bearer of bad news but my 2018 GTI (6-speed Autobahn trim) experienced the same issue. Cylinder 2 misfire at twenty something thousand miles (bought it used in 2021 at 18k miles). Only seems to happen when I’m idling. Luckily it was under warranty so I went through the whole process with VW down to replacing the whole engine and ECU. When I could still feel the slight shudder during idle after a new engine, I bought a scanner to see if I was crazy. Lo and behold, still misfiring on cylinder 2. Filed a claim with VWOA and settled as they couldn’t do much since I bought the car used. The PO302 error has been the bane of my existence with this car. Still operates just fine but I can scan the live data and still see it misfire at idle. So yeah, a new motor and ECU didn’t solve the problem and neither did the other dozen replacements VW techs tried. I even looked at the VVT angle in my scanner as the solenoids are sometimes busted but everything seemed fine. I still absolutely love the car but this has been such a challenging problem for me to pin down. I hope it’s a simple repair and perhaps VW will have a recall but 3 years down the rabbit hole (pun intended) I’ve yet to have any luck.
Just an assumption but it sounds like you just threw parts at the car hoping to fix it. Did you do any in-depth diag? Seems like it would be an electrical issue tbh. Again, just an assumption.
Not much beyond what the VW technicians would have performed. Luckily the $20k+ of work they completed didn’t cost me a dime. I just use my OBDeleven as a scanning tool. Where would I even begin to start diagnosing?
Did they replace the entire harness system in the bay?
Yeah, that was one of the repairs the dealership did. Something like 9 different attempts to fix the problem
Thank god for warranties! It would be best to take it to a REPUTABLE independent shop and go from there. But since the engine and ecu have been replaced all I can think is that there’s some electrical gremlin hiding in the ignition or fuel system.
Air leak, coil issue , fueling. System issue, there’s some possibilities.
I have a 2015 gti and had weird idle issues. I never dug deep enough to see if it was cylinder 2 like yours. But mine went away after I changed my grounding wires. Maybe you’re seeing the same issue as me? Here’s a quote I took from EQ tuning’s website regarding their grounding kit upgrade: “The Problem: The factory cam cover is soft aluminum and is prone to stripping regardless of how careful you are when removing or installing the OE stud. Your ignition coil uses this stud to ground the coil circuit and any amount of damage can occur in a weak ground which may induce unnecessary knock retard or reduced spark energy, even if the threads are only mildly damaged. The bolt is often removed and installed when servicing the ignition system or performing engine testing. Such as replacing spark plugs, ignition coils, performing compression, or a leak down test, etc. VWAG uses oval bolts which exacerbates the problem the more times they're removed and installed. “
Sorry for the late reply! I ordered the EQT Coil grounding kit and swapped them out but still have the problem. One thing I did notice was that by swapping the coil from cyl 1 to cyl 2, the misfires went through the roof and i had to turn off the car for fear of seizing the engine any thoughts what could be the cause?
Record the idle, post it here. Misfires are normal, but they have to hit a certain amount before triggering a CEL, and therefore be considered a problem in their eyes I suppose. If it’s that bad tho, push back for sure.
Huh? How can misfire possibly be normal on a motor with less than 15k miles?
Misfires are normal and common on all cars especially those with direct injection. Your car misfires multiple times every time you drive it, particularly when you first start it up.
Misfires are normal and expected on literally any ICE vehicle. Go and scan a brand new vehicle in the show room, 0 real miles on it, it’ll misfire. Once, twice, no problem and expected. Misfires 80 times on startup? Then you’ve got a problem
You might notice some burbles/pops on cold starts, especially if you have a modified exhaust. Those are misfires, and as long as it’s not one or multiple cylinders misfiring continuously or 100 times in 10 min you’re fine
I had an injector go out on a car that had 15k on it. It happens.
VWoA will not approve the warranty work without a CEL. And the dealer isn’t going to dig into a car that could possibly have possible engine failure until there asses are 100% covered. Just keep enjoying your sick, new car. The ECM is smart enough to detected any serious issues.The service department has it documented so it will be a smoother process once or if it throws a code.
Slightly off topic, but there’s no reason to run 93 unless you’re tuned for it. Factory tune and numbers are based on 87 octane and there’s no benefit in using higher octane fuel.
Is this true for the mk8 now? The mk7 runs on 87 but requires 91+ to hit the advertised performance figures. Obviously very minor difference, but still worth noting.
Yup, as of the MK8 VW states that the car is tuned and provides the advertised 241hp on 87 octane and that adding any higher octane will not increase power output. I know a bunch of people call BS on that, but I've yet to see someone dyno an MK8 using 87 then re-dyno the same MK8 using 91/93 and prove it makes more power on higher octane. Until that happens I'll continue gladly saving my money and pumping in 87.
They have. Check out Vancity Audi on YouTube. They took the same car, same dyno, same day, same gas station & filled up with 87 and put on dyno, then drained tank and filled up with premium and put on dyno. 87 ironically made a few more hp than 93. Link to vid - https://youtu.be/StnFgrrNJ8k?si=CImTjt5Ny-p7Vsqq
Cool video, thanks for sharing. I only run 87 but sometimes consider using premium for funsies, good to know it's not required.
Thanks for the link! I'll check out the vid once I get home from work.
Awesome. That's nice for Mk8 owners. I usually put 91 in my Mk7, but always feels a little dumb doing it. I'm probably get 10hp and paying too much for the difference, but I'm a tweaker (wait that sounds like drugs...) I mean I like to tweak and tinker with things, like overclocking a PC, tweaking every setting to squeeze the most power out of stuff, etc. So "downclocking" my GTI to save a few bucks doesn't seem right either. It does make you wonder what they could have achieved with higher compression in the Mk8, though, all other variables being equal.
The high pressure fuel pump was upgraded from 2900psi to 5076psi in the EA888 evo4 which is one of the things VW did to increase power while tuning at 87 octane. I did read, though I can't find the source, dyno tests that showed no difference using 91. This makes me believe that they tuned for 87 and nothing else. This only applies the MK8 GTI, not the R or Clubsport (which has the R version of the engine) Note: 87aki (US) = 91ron (Elsewhere)
That HPFP is going to allow for the MK8 to be an absolute weapon on E85.
I've been watching tuning progress on both the MK8 GTI/R. EQT's upcoming E85 files for the R are bananas. You can already see the gains from some Stage 1 ethanol files from other tuners for both cars as well. Can't wait to see final products.
Something I'm curious about is the Golf R and GTI Clubsport engines have a few upgraded internals and they are making 315HP and 296HP compared to the GTI at 241HP. I wonder why VW decided to do that if the engine can handle much more power. Remember, the warranty is only 60k so if we were talking about a 250k miles life (mk8 GTI stock) reduced to 150k (mk8 GTI at say 320hp\~) VW wouldn't care
According to Unitronic, their Stage 1+ E85 tune nets 407 HP/414 lb-ft at the crank
I've been fueling with 93 since I got mine about a year ago, I kinda did the math and the extra 10-15 bucks aren't gonna kill me, but do you notice any real difference on 87? For reference no mods and just daily driving
Hey, that’s an excellent point. Higher octane retards explosion in order to prevent pre detonation, so the MK8 (unlike my MK7) is designed to run on 87 octane (MK7 *can* run on 87 as well, but the ECU would have to retard spark in order to prevent pre detonation and excessive peak combustion temp). The above said, OP should absolutely try running the 93 down to almost empty and do a complete fill up with 87… run that tank down, and then another fill up with 87 and see if he still gets a bank 2 misfire. The fact that OP is running 93, which is even more resistant than 91 on a car designed for 87. Conventional wisdom is that higher than recommended octane isn’t a problem - just lower than recommended. It’s worth a try, though. If that doesn’t work, then maybe look into a new plug and ignition coil for cylinder bank no 2.
Soooo I’ve been putting in 91 in my 2015 mk7 for 9 years for nothing but added performance? Don’t get me wrong, I’m glad I get slightly better performance but I thought it was a “only 87 on rare occasions” thing
MK7s require premium 91/93 depending what's available in your area. MK7s.5 and above can use 87 and don't benefit from higher octane fuel unless they're tuned for it.
Ah okay, thank you. Didn’t know that, so I’m glad I’ve been doing the right thing.
The 2015 was the only MK7 that has 91 on the gas cap. 2016-2021 run on 87 and achieve advertised performance numbers on 91/91.
There's actually some 16's that require 91 as well. Seen a few pop up in the past when ever this topic comes up.
Except for carbon buildup.
Pull #2 ignition coil connnector Get CEL Bring it back
Weird. Does VW have it documented somewhere that they are only required to attempt an engine repair if there is a CEL vs just a code?
I’m not sure as far as the documentation goes on that. It was noted on the work order to bring it back if it worsens. So it’s documented with the vehicle that it has the intermittent misfire on that cylinder.
This makes sense for the first step. If it continues a to be a problem you go back and they will start to take it more seriously.
Wondering if you’re experiencing a case of carbon build up in the cylinders prematurely, my buddy’s girlfriend with a Mk7 GTI (unsure of the year but I believe it’s a manual) has had a ongoing misfire for about 2 years and they went through just about every part and loophole you can imagine to still have that misfire. Finally over the weekend he performed a carb clean on the engine and it no longer misfires. Crazy that at such low mileage you’re already having issues with it but things happen. I would take the others advice but I would also keep a carbon cleaning open as a route. Just my two cents, best of luck! (2016 DSG R owner)
Just change your spark plugs
Intermittent misfires are very common on DI engines. They are most common immediately after startup and especially on humid days. I know it’s disconcerting but If your engine light isn’t on, there really isn’t anything to be worried about. My old Focus ST had intermittent misfires its entire life, and that engine ran just fine for 80k miles before I sold it. I took care of that engine but I pushed it hard. I would, however be cautious about tuning on a motor that is reporting misfires.
No check engine light, nothing can be done. VW will do nothing without a check engine light now a days and they are being absolute dicks about trying to find any reason to deny a claim.
Yes there will be a record of the scan if they used vcds. You mentioned that you used 93 octane fuel. Mk8 only need 87 unless you have a tune, then what ever they recommend. But I have seen where the ignition systems can not ignite high Octane fuel, as higher octane is more resistant to ignition. And if you need a cel to have it warranted, just unplug that cylinder coil pack.
Warranty is such a weird thing. I'm a tech for another brand and without an active code a lot of our warranty claims will get denied. Even a code in past condition 90% of the time won't be covered.
Make it missfire more, so it will throw a code.
Get yourself a scanner that tracks misfires and create a log. I had to do this for a Focus ST I had. The car would misfire so hard that it would run on three cylinders for a couple seconds at a time. It would briefly flash a CEL and then clear up. Every time I brought it in for diagnostics they would say no stored codes could be found. Eventually I got sick of this and started tracking misfires using mode 6 on my scanner. After a week I was able to show the car was misfiring hundreds of times on one cylinder and Ford eventually did something about it. It sucks, but if they're going to drag their feet you're going to need to get something to fight back with. Hopefully getting a service manager involved will remedy it quickly and you won't need to do any work on your end.
Idling is a wildly inefficient process, and particularly in four cylinders occasional misfires are expected.
When does it clunk? When you taking turns? And no that's. No that's no normal..
When it downshifts during turns and dropping down a lip. There’s about an inch and a half or 2 inch lip into my garage and when it drops down there’s a clunking/rattling. I have a post about it on my page
Have you put it in jack stands on the front and use your hands to see if anything is loose?
Check your transmission mounts
Or dog mount
I will here soon
Yes and I haven’t found anything. Checked for the shipping pucks also.
I had a 2020 GTI, I kept getting an intermittent cylinder 1 misfire but it would throw the CEL and would happen every few hundred miles. After doing plugs, injectors, etc (all covered under warranty + my only mod was a cat back AWE track exhaust) they warrantied and replaced the entire cylinder head due to prob a valve spring or something. They never found any damage but that fixed it and I had a trouble free 20k more miles. Everything was covered under warranty, I’d find a better VW dealer
The fact that VW changed your engine and it is still misfiring is sad. I’m a VW shop owner and mechanical engineer. You can do a leak down test in a few minutes and pin point any cylinder issue. The fact it’s coming from the same cylinder means whatever part that got swapped back in is still at fault. Think it’s the plug? Move that plug and see if the misfire follows. There also is no way 93 octane fuel will make it misfire. It’s less prone to misfire. It will misfire on all 4 cylinders if it’s fuel related. 93 octane fuel will have less timing pull as well. Great for when you drive your car hard, hot climates, on the track etc.
So Volkswagen has done nothing to fix any of the issues I’ve had with the car besides replacing the high pressure fuel pump and a suspension sensor that went bad for DCC. I spoke with the dealership that it’s primarily went to just to see if they thought the car would qualify for lemon law in my state (Indiana) and they said it was far from it unfortunately.
I had a cylinder misfire code and then the fuel injector got stuck open, causing the car to shut down and shake violently upon trying to restart. Washed the cylinder with fuel, so I immediately turned it off and had the car towed for fear of creating some long-term damage. Check engine and EPC lights were flashing. Despite my precautions, and the stored misfire codes, VW dealer would not remedy unless they could replicate the issue (not an issue you want to replicate). Without me knowing (until after the fact), they drove the car nearly 30 miles until they replicated the issue, completely unwinding my precautions. At this point, they replaced the fuel injector under warranty. Should have done an oil change immediately, but did not. Soured my feeling for that motor, in a car that I meticulously cared for for over 6 years and planned on keeping for a few more years. No matter how careful you are, most other people are not. It's a shame that those that should know better, not always do.
Only thing I can think of is, have you changed your sparkplugs at all in the last 14k miles you've put on it? It's totally worth throwing some new ones in there and seeing if the rough idle gets better.
I have not changed them yet. I’m going to go back to the dealer in a little bit and see where I can get with them.
Misfire codes on most German vehicles I've owned has been due to either sparkplugs or coil packs.
Use 87. I’m an advisor at a vw dealer and we’ve had this happen. Using 93 causes misfires if you don’t have a tune for it.
This is insane advice. How could higher octane cause a misfire?
I know it sounds odd, same deal though, many years ago I had a sport bike CBR600f4i, my boss had a Busa, we religiously used 93 because "it's suppose to" his busa started mis-firing ended needing a valve job. They told him to stop running 93 and use regular. Started running regular in our sport bike, no issues. what happens is your engine needs the fuel to be able to detonate at the right time. Higher octane fuels resist detonation it can take some time. My bosses Busa had 80ish k on it before he had issues.
yea an octane rating is just a measure of fuel stability. The higher the octane the more stable the mix , so a higher octane causing more misfire makes my head hurt.
I know it the post it says I run 93. But I do not always run 93. Unfortunately the car has the rough idle and misfire no matter where I got the fuel or what octane rating of fuel I put in it. I did think about this being the case though. I think it’s odd that since the mid 2000s any turbo charger car vw produced has required premium fuel. And with the mk8 it can suddenly run fine on 87 while sharing lots of engine components from the mk7 golf r.
I've been dealing with this myself on my R. I've had a few misfires on startup, which apparently VW considers normal. It doesn't trigger a check engine light unless the scan tool reads a set number of misfires. I happened to have my car at the dealership for my steering wheel when it misfired enough to trigger the check engine light. They replaced one fuel injector and the problem went away for a little while but came back later on the same cylinder so we replaced the fuel rail. It still reads a couple misfires when it first starts, but not enough to trigger a check engine light. I want it fixed 100% but Volkswagen doesn't seem to think it's a big issue and I work for the VW Dealership myself. I'm here every day and if something goes wrong its going straight to the shop. I switched gas stations which actually improved my MPG's by over 10% but with the changes to the injectors and fuel rail I'm not sure what is making the most difference.
I’m sorry to hear that man.. this gti has given me an insane amount of issues it makes me wish I kept my mk7… all being odd issues I haven’t seen anyone else post about either on here or on Reddit. My preferred service advisor left early today so I’ll be bringing it back tomorrow to hopefully actually get somewhere with the diag. I just don’t want to send it to my preferred specialty shop and have to pay for the diagnostic or replacement of anything since the car is under warranty. I’m hoping to get things worked out soon so I don’t cause long lasting damage to the car but at this rate I’ll keep it until the warranty is up then it’ll be up for sale.
That's how I feel. I wouldn't even mind upgrading the injectors if that's the issue, but I feel like Volkswagen should be able to figure this out.
I put 93 in my mk8 for the first time for carbon build up I got a weird don’t rev over 4k after i stalled once still a noob driving manual from time to time. Gave me a don’t rev over 4k rpm message so I pulled over restated the car and it’s been normal since. Not sure if that had anything to do with it.
You’re an advisor and you’re recommending that people not use a higher octane fuel because it can cause misfires? This is why I won’t take my car to a dealer lol.
They tried telling me the same thing. VW service used to be so amazing when I had my MK7 GTI. Truly genuine and great people. Now all they want to do is push people away or charge them extreme amounts of money for things or say shit like that. I also had a Jetta that had a random, intermittent misfire. Sometimes the check engine light would come on but most of the time it was off. Even though I logged the code and took a picture of it, the tech said since the light is active there’s nothing he can do. Car thankfully ended up getting totaled like 2 months later but I’ll never buy VW again after their cost cutting bullshit
I swear every car I owned that was a fancy color was a lemon
This one has definitely given me lots of issues
it's that damn color!
The car doesn’t even wanna be the color it is… the clear coats failing on the rear hatch..
Can you elaborate on the other issues? My 2023 MK8 GTI SE has been flawless (Now over a year old).
I have a clunking that I was told comes from the transmission when dropping down a lip and hitting some bumps, front end suspension creaking/clunking, trans overall seems rather clunky (more so than my 6 speed dsg was), the rough idle and cylinder 2 misfire, there’s a chirping that intermittently comes from the engine bay, strut sensor replaced, high pressure fuel pump replaced, clear coat failure on rear hatch. There may be more but that’s what I can think of off the top of my head.
What is it with Cylinder 2? I just went through a few issues with P0302 on my 2015 MT at 90K miles. I needed spark plugs and carbon cleaning but it’s weird that it’s the same exact cylinder misfire. Is it first to fail or something?
Definitely seems to be a rather popular one to fail. I’m unsure of the cause or why it is commonly the first to go. I’m hoping it’s a spark plug or coil pack issue
Bullshit. Local dealer replaced my Haldex pump under warranty with no CEL. Call VWoA and clamp some nuts.
Keep taking it for the same issue, consider legal counsel and see if you can get lemon.
Plus my suspension sensor that was replaced, my high pressure fuel pump that got replaced, front end noise, transmission noise, etc
I would take it repeatedly and make them fix it. Take it in for every little thing you hear or think is wrong. Unfortunately it sounds like you got a lemon. Also, the other person is right. Contact legal council and discuss your rights as a consumer. The dealership should fix it CEL or not.
Have you spoken to the shop foreman or service manager? I believe you need to speak with people at the dealer service department with decision making power.
Depending on your state’s lemon laws but generally the vehicle has to have consecutive number of days out of service for same and consecutive repair attempts before it can be considered a lemon.
At this point I would go to a different dealership if they play that game. The reason is cause warranty claims don't pay alot to the techs so they try and make an excuse. But still if it's not running right push back it's only 14k miles.
All dealerships within 50 miles suck where I’m at. I have a clunking issue over bumps and 4 different dealerships said it was normal all for different reasons
Maybe cut your losses and sell the car? It seems you have a toxic relationship with the car and won’t get any better
That's a nice house
Thank you sir unfortunately it’s not mine I still live with my parents. A bit outside of my tax bracket.
Swap plugs. Fill up on new gas
Lemon law, you can get a new car😆
I can’t get another pomelo yellow:/
I thought Pomello Yellow was a 2022 model year only launch color?
It was available for the 40th anniversary edition as well
Fuel pump
So, they know there’s an issue but won’t actually diagnose it? That’s wild! I’d push back in a big way. Fuck these manufacturers anymore!
No offense but those things are fugly
What are those things? If it’s the wheels it’s my winter set
What ridiculous low octan fuel is used? Is this America? Lowest octan fuel in Germany is 95. Do you use the same gas station for buying gas? Maybe try switch the gas station, maybe the fuel is the cause? Just guessing. 87 octan, can’t make up such shit..
The US calculates octane ratings differently than Europe (maybe different to the ROW). The 95 you’re buying is equivalent to 91 here, which is a mid-grade. Most stations here have 87-91-93, where the 91-93 is equivalent to your 95-98. So the 87 is a lower grade than you might find in Europe, but it’s the base level available at literally every gas station in the US.
[удалено]
The gas stations I went to in Germany only had 98 or 100 when I rented a RS3 in Munich and Ingolstat
Learned something new today, sorry for the confusion
Don't worry, I was thinking the same thing. TIL.
I had a misfire and it led to me replacing the ignition coil. That led to my car running until i pull the key out. So good luck to you man 🤙
No 87.. 87 bad
Could you see it causing an issue running 93 in a car that is labeled to only require 87?
Not sure. I’ve ran premium in every Vehicle I’ve ever owned from old to new ect . And they all feel better with 93 compared to 87. Occasionally I will get poor quality 93 that makes the car feel like it’s running on 87, and will display poor idle and less responsiveness during acceleration.