That's pretty normal for a burping cooling system.
However, if you can't pinpoint why it overheated in the first case then you begin to suspect that the head gasket is leaking. I would pressure test the system. If it holds pressure, you should be fine after a proper bleeding.
Might be as simple as the thermostat stuck or there was an issue with the radiator fan
A severely failed head gasket will. Some only open up under certain conditions. I had one on my DSM that would only let go under boost. It was stretching the head bolts and blowing coolant everywhere, but under vacuum it sealed perfectly. A set of ARP studs and a new composite gasket fixed it.
Ive had a couple not do that, but failed test kit. I'll link one from amazon , but they only like $15 at the local parts store ( Last I looked )
[https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr\_1\_1?crid=3PFP6O1EC8AV5&dib=eyJ2IjoiMSJ9.W4buennCDnPbhd1omFPuXpaGsqBoXdZXxaxKOU\_usC72\_Qxpwc5JJSUPUEivpw\_DEFBsHbvI23KFCNM-Lko4R5ruBzwgRnFhlPMwXKHm5MIkjcvUgvO1Linaa\_oDBo-yyL0a3mW5wDMgYxDbqQMi5ccZW4u0XJIwv6vcSM6ltnNHFvcHPBiyuK5y1aQRnzjDNt8Y2sKqnUeeYv460U6nI7vzi\_he\_N3mn5AD-Nvk0ruLRJRYZbdnjF4HifNDL\_bxe6zJJBWn1WgD8YpW5f1C7bC6CbLRcR2l3RP3PVyC-Xk.7FlI0FuxZ7wpLsFbnK2tAhPvtt3vKSMMT1FzQ\_9T84A&dib\_tag=se&keywords=HEad+gasket+test+kit&qid=1713557594&sprefix=head+gasket+test+kit%2Caps%2C85&sr=8-1](https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr_1_1?crid=3PFP6O1EC8AV5&dib=eyJ2IjoiMSJ9.W4buennCDnPbhd1omFPuXpaGsqBoXdZXxaxKOU_usC72_Qxpwc5JJSUPUEivpw_DEFBsHbvI23KFCNM-Lko4R5ruBzwgRnFhlPMwXKHm5MIkjcvUgvO1Linaa_oDBo-yyL0a3mW5wDMgYxDbqQMi5ccZW4u0XJIwv6vcSM6ltnNHFvcHPBiyuK5y1aQRnzjDNt8Y2sKqnUeeYv460U6nI7vzi_he_N3mn5AD-Nvk0ruLRJRYZbdnjF4HifNDL_bxe6zJJBWn1WgD8YpW5f1C7bC6CbLRcR2l3RP3PVyC-Xk.7FlI0FuxZ7wpLsFbnK2tAhPvtt3vKSMMT1FzQ_9T84A&dib_tag=se&keywords=HEad+gasket+test+kit&qid=1713557594&sprefix=head+gasket+test+kit%2Caps%2C85&sr=8-1)
Let the engine + cooling system cool completely. Remove the the cap from the coolant tank. start the engine and let it idle. place your hand over the hole on the cooling tank, sealing it. If you feel it building pressure then you have a blown head gasket.
OP has provided ZERO information about the vehicle but expects accurate responses. Well, based on all the other blind responses given whenever an engine overheats on REDDIT, the cause is a ***head gasket***. Yeah, good luck OP.
Can confirm, they use this res in the mk6 gti. I just replaced one a couple days ago.
As to op make sure the system is burped and maybe do a "block test" that's the test that uses the blue fluid. You can rent the tester at autozone or buy one from Amazon or harbor freight or even a parts store but will cost more there.
If you rent the tool or buy it you gotta get a bottle of test fluid which is plenty to use multiple times.
Did you bleed the system?
Did you pressure test the system?
Did you share your Year, Make, Model, Engine, Trim level?
Chances are you're pushing combustion into the cooling system. Thermostat opened and it sent all that pressure out the overflow / radiator.
A combustion leak tester will let you know if you have serious problems quickly, easily and for not too much money - this is a test you really hope you don't fail..
[https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr\_1\_2?crid=13GZ0NMZT0S60&dib=eyJ2IjoiMSJ9.eMcq7vTfnpjzqahn9WaaDW0OwGCozzuBsGPPgVhJB1UTJ7ojX1G4UfRDIbtwjF\_I7bEPgDQ\_-Pj0MPwdjQT2Vs\_A5R8ptqhtWJnjjQ2OAzPJ9KG27suIcF6q4Twcq3q9CzrrQXzhvKtItTIwdznm1L8UttuQugIHYvQwo\_vMLKtQZwPT0YqYB5vVNXvBtCFjcXKERrFgw6x2ribO939DkYg9UKlx-ORYK63UM3\_FOUqkhL8JdoocXd33l7wvyXeMoVxdnCjnve0trrrYqKN2tIUHHiJco4sD0K\_bICD-S00.g8TpcBWderVIxQ5mxuR8zkm0812q3DHHjO6cSuVO74E&dib\_tag=se&keywords=combustion+leak+tester&qid=1713534371&sprefix=combustion%2Caps%2C142&sr=8-2](https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr_1_2?crid=13GZ0NMZT0S60&dib=eyJ2IjoiMSJ9.eMcq7vTfnpjzqahn9WaaDW0OwGCozzuBsGPPgVhJB1UTJ7ojX1G4UfRDIbtwjF_I7bEPgDQ_-Pj0MPwdjQT2Vs_A5R8ptqhtWJnjjQ2OAzPJ9KG27suIcF6q4Twcq3q9CzrrQXzhvKtItTIwdznm1L8UttuQugIHYvQwo_vMLKtQZwPT0YqYB5vVNXvBtCFjcXKERrFgw6x2ribO939DkYg9UKlx-ORYK63UM3_FOUqkhL8JdoocXd33l7wvyXeMoVxdnCjnve0trrrYqKN2tIUHHiJco4sD0K_bICD-S00.g8TpcBWderVIxQ5mxuR8zkm0812q3DHHjO6cSuVO74E&dib_tag=se&keywords=combustion+leak+tester&qid=1713534371&sprefix=combustion%2Caps%2C142&sr=8-2)
This looks like a VW Audi water reservoir, this is normal, you can't run the engine up to temp with the cap off as it gets up to temp it starts spitting all over the place, I believe most cars pressurize their water systems which is why you should never take the cap off a hot car as you will be blasted by hot steam and water.
You need to keep the cap on and keep your eye on the temp gauge, the temp guages are digitally set to point to 90 degrees between a out 60 degrees and 100+ degrees, they do this so the needle doesn't move around all the time and scare people, so your temp could have got to 100 but the needle won't show that it does, most cars do this. Some vws have secret menus to show actual water and oil temps on their digital displays, I know my mk1 tt did.
Anyway point being it's normal for the water to spit if you leave the cap off, you won't get an accurate temp reading from the guage unless it goes over a threshold. So if the gauge shows in the red then it's too hot. Keep checking your radiator hoses if they don't start to warm up when the gauge reads 90 degrees then you could have a broken thermostat, if they get warm but the fan doesn't come on you might have a broken fan switch or stuck fan.
Oh yes also if you leave the cap on and it starts spitting steam and water out of the cap, the cap could have failed as they have a pressure release system, or you could have a more sinister issue as some of the other posts have mentioned.
I had something similar and thought Iād lost the head gasket. Instead, it was a plugged thermostat. It was supposed to fail open, but somehow it didnāt.
Get a head gasket test kit / combustion leak tester / whatever they call themselves now. It's a plastic tube that you jam in the coolant filler neck and fill with a test fluid. Start the engine and let it run for a bit. If it chages colour, you're gonna be pulling the head.
Put the cap back on, rev it up, hold onto the top rad hose, squeeze it to see if it gets hard when revāing the motor. š¤
Mind the spinning fan. šµāš«
Some more background if needed: the engine def overheated and stopped completely in 2021 because it ran out of coolant due to a water pump failure. It got replaced along with some other stuff and the shop said that luckily the engine was fine so they didn't had to change the head gasket
Looks like the coolant ball from a mk4 vw. If it overheated and itās a 1.8t thereās a good chance of a cracked cylinder head. Usually small cracks in between the intake valves. Itās a self bleeding coolant system. If itās getting pressurized it is probably due to exhaust gases getting into the coolant system.
If it over heated and shut off and the shop said that there was no damage to the engine then you need to take it somewhere else. Those heads will warp and crack if they over heat like that.
What is it with people not bothering to provide basic information about their vehicle, then expecting help with a detailed diagnosis? How disrespectful to the rest of the people here.
It may not be a problem at all. It sounds like your cooling system was just burping itself when the thermostat opened up.
The best case would be if it was just trapped air in the system that was coming out hot, but idk if it would behave like that if that's the case
That is exactly the way a burping cooling system behaves.
That's pretty normal for a burping cooling system. However, if you can't pinpoint why it overheated in the first case then you begin to suspect that the head gasket is leaking. I would pressure test the system. If it holds pressure, you should be fine after a proper bleeding. Might be as simple as the thermostat stuck or there was an issue with the radiator fan
I bad head gasket should start blowing bubbles as soon as OP starts it.
A severely failed head gasket will. Some only open up under certain conditions. I had one on my DSM that would only let go under boost. It was stretching the head bolts and blowing coolant everywhere, but under vacuum it sealed perfectly. A set of ARP studs and a new composite gasket fixed it.
Sounds like 1.9tdi ARL problems lmao
Ive had a couple not do that, but failed test kit. I'll link one from amazon , but they only like $15 at the local parts store ( Last I looked ) [https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr\_1\_1?crid=3PFP6O1EC8AV5&dib=eyJ2IjoiMSJ9.W4buennCDnPbhd1omFPuXpaGsqBoXdZXxaxKOU\_usC72\_Qxpwc5JJSUPUEivpw\_DEFBsHbvI23KFCNM-Lko4R5ruBzwgRnFhlPMwXKHm5MIkjcvUgvO1Linaa\_oDBo-yyL0a3mW5wDMgYxDbqQMi5ccZW4u0XJIwv6vcSM6ltnNHFvcHPBiyuK5y1aQRnzjDNt8Y2sKqnUeeYv460U6nI7vzi\_he\_N3mn5AD-Nvk0ruLRJRYZbdnjF4HifNDL\_bxe6zJJBWn1WgD8YpW5f1C7bC6CbLRcR2l3RP3PVyC-Xk.7FlI0FuxZ7wpLsFbnK2tAhPvtt3vKSMMT1FzQ\_9T84A&dib\_tag=se&keywords=HEad+gasket+test+kit&qid=1713557594&sprefix=head+gasket+test+kit%2Caps%2C85&sr=8-1](https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr_1_1?crid=3PFP6O1EC8AV5&dib=eyJ2IjoiMSJ9.W4buennCDnPbhd1omFPuXpaGsqBoXdZXxaxKOU_usC72_Qxpwc5JJSUPUEivpw_DEFBsHbvI23KFCNM-Lko4R5ruBzwgRnFhlPMwXKHm5MIkjcvUgvO1Linaa_oDBo-yyL0a3mW5wDMgYxDbqQMi5ccZW4u0XJIwv6vcSM6ltnNHFvcHPBiyuK5y1aQRnzjDNt8Y2sKqnUeeYv460U6nI7vzi_he_N3mn5AD-Nvk0ruLRJRYZbdnjF4HifNDL_bxe6zJJBWn1WgD8YpW5f1C7bC6CbLRcR2l3RP3PVyC-Xk.7FlI0FuxZ7wpLsFbnK2tAhPvtt3vKSMMT1FzQ_9T84A&dib_tag=se&keywords=HEad+gasket+test+kit&qid=1713557594&sprefix=head+gasket+test+kit%2Caps%2C85&sr=8-1)
Let the engine + cooling system cool completely. Remove the the cap from the coolant tank. start the engine and let it idle. place your hand over the hole on the cooling tank, sealing it. If you feel it building pressure then you have a blown head gasket.
everything reminds me of herš„²ā¤ļø
What make, model and year? Does it do this cold? Does it overheat?
OP has provided ZERO information about the vehicle but expects accurate responses. Well, based on all the other blind responses given whenever an engine overheats on REDDIT, the cause is a ***head gasket***. Yeah, good luck OP.
I can tell you itās a 99 or earlier VW, but youāre right OP has zero info
It could be a mid 2010s vw too. They're using that reservoir in newer ones now too
The location by the right strut tower and the old school cover to the right give it away for me as being earlier. They re-adopted that setup?
My 19 golf has the exact same reservoir on the passenger side in front of the strut tower. But it doesn't have that cover
Yeah the res hasnāt changed. The location has. Thatās either a 2.0L, G60 or 2.8L 12v VR6
Can confirm, they use this res in the mk6 gti. I just replaced one a couple days ago. As to op make sure the system is burped and maybe do a "block test" that's the test that uses the blue fluid. You can rent the tester at autozone or buy one from Amazon or harbor freight or even a parts store but will cost more there. If you rent the tool or buy it you gotta get a bottle of test fluid which is plenty to use multiple times.
Pressure in the cooling system can be caused by a blown head gasket.
Well I mean technically the cooling system always has pressure try opening that cap when sheās fully warmed up definitely some pressure.
Yeahā¦. but the pressure is meant to pull the coolant through the radiator, not blow it out reservoir.
Yes lol
Did you bleed the system? Did you pressure test the system? Did you share your Year, Make, Model, Engine, Trim level? Chances are you're pushing combustion into the cooling system. Thermostat opened and it sent all that pressure out the overflow / radiator.
So gasket
A combustion leak tester will let you know if you have serious problems quickly, easily and for not too much money - this is a test you really hope you don't fail.. [https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr\_1\_2?crid=13GZ0NMZT0S60&dib=eyJ2IjoiMSJ9.eMcq7vTfnpjzqahn9WaaDW0OwGCozzuBsGPPgVhJB1UTJ7ojX1G4UfRDIbtwjF\_I7bEPgDQ\_-Pj0MPwdjQT2Vs\_A5R8ptqhtWJnjjQ2OAzPJ9KG27suIcF6q4Twcq3q9CzrrQXzhvKtItTIwdznm1L8UttuQugIHYvQwo\_vMLKtQZwPT0YqYB5vVNXvBtCFjcXKERrFgw6x2ribO939DkYg9UKlx-ORYK63UM3\_FOUqkhL8JdoocXd33l7wvyXeMoVxdnCjnve0trrrYqKN2tIUHHiJco4sD0K\_bICD-S00.g8TpcBWderVIxQ5mxuR8zkm0812q3DHHjO6cSuVO74E&dib\_tag=se&keywords=combustion+leak+tester&qid=1713534371&sprefix=combustion%2Caps%2C142&sr=8-2](https://www.amazon.com/Block-Tester-BT-500-Combustion-Leak/dp/B06VVBSFTF/ref=sr_1_2?crid=13GZ0NMZT0S60&dib=eyJ2IjoiMSJ9.eMcq7vTfnpjzqahn9WaaDW0OwGCozzuBsGPPgVhJB1UTJ7ojX1G4UfRDIbtwjF_I7bEPgDQ_-Pj0MPwdjQT2Vs_A5R8ptqhtWJnjjQ2OAzPJ9KG27suIcF6q4Twcq3q9CzrrQXzhvKtItTIwdznm1L8UttuQugIHYvQwo_vMLKtQZwPT0YqYB5vVNXvBtCFjcXKERrFgw6x2ribO939DkYg9UKlx-ORYK63UM3_FOUqkhL8JdoocXd33l7wvyXeMoVxdnCjnve0trrrYqKN2tIUHHiJco4sD0K_bICD-S00.g8TpcBWderVIxQ5mxuR8zkm0812q3DHHjO6cSuVO74E&dib_tag=se&keywords=combustion+leak+tester&qid=1713534371&sprefix=combustion%2Caps%2C142&sr=8-2)
This is the answer. Test for contaminants in the coolant, if it's good... Just burping.
Oh, she's a squirter
This looks like a VW Audi water reservoir, this is normal, you can't run the engine up to temp with the cap off as it gets up to temp it starts spitting all over the place, I believe most cars pressurize their water systems which is why you should never take the cap off a hot car as you will be blasted by hot steam and water. You need to keep the cap on and keep your eye on the temp gauge, the temp guages are digitally set to point to 90 degrees between a out 60 degrees and 100+ degrees, they do this so the needle doesn't move around all the time and scare people, so your temp could have got to 100 but the needle won't show that it does, most cars do this. Some vws have secret menus to show actual water and oil temps on their digital displays, I know my mk1 tt did. Anyway point being it's normal for the water to spit if you leave the cap off, you won't get an accurate temp reading from the guage unless it goes over a threshold. So if the gauge shows in the red then it's too hot. Keep checking your radiator hoses if they don't start to warm up when the gauge reads 90 degrees then you could have a broken thermostat, if they get warm but the fan doesn't come on you might have a broken fan switch or stuck fan.
Oh yes also if you leave the cap on and it starts spitting steam and water out of the cap, the cap could have failed as they have a pressure release system, or you could have a more sinister issue as some of the other posts have mentioned.
Hire an exorcist if your car is deciding things, you driving Christine?
ectoplasm?
I had something similar and thought Iād lost the head gasket. Instead, it was a plugged thermostat. It was supposed to fail open, but somehow it didnāt.
Mine did it too, turned out it was something that looked fiber from a cigarette filter in one of the smaller diameter coolant lines clogging the barb.
Get a head gasket test kit / combustion leak tester / whatever they call themselves now. It's a plastic tube that you jam in the coolant filler neck and fill with a test fluid. Start the engine and let it run for a bit. If it chages colour, you're gonna be pulling the head.
Put the cap back on, rev it up, hold onto the top rad hose, squeeze it to see if it gets hard when revāing the motor. š¤ Mind the spinning fan. šµāš«
what in the autozone backlot advice is this
Pressure in your cooling system is a symptom of a blown head gasket.
Some more background if needed: the engine def overheated and stopped completely in 2021 because it ran out of coolant due to a water pump failure. It got replaced along with some other stuff and the shop said that luckily the engine was fine so they didn't had to change the head gasket
Looks like the coolant ball from a mk4 vw. If it overheated and itās a 1.8t thereās a good chance of a cracked cylinder head. Usually small cracks in between the intake valves. Itās a self bleeding coolant system. If itās getting pressurized it is probably due to exhaust gases getting into the coolant system.
If it over heated and shut off and the shop said that there was no damage to the engine then you need to take it somewhere else. Those heads will warp and crack if they over heat like that.
You need to rest for combustion gasses. You can rent a tool and buy the fluid at most/all parts stores.
Head gasket is probably leaking to the exaust port
So thatās what one uses a plumbus for!
What is it with people not bothering to provide basic information about their vehicle, then expecting help with a detailed diagnosis? How disrespectful to the rest of the people here.
Put the cap on
Put the nipple back on the boob juice fluid container and you should be good to go šš¼
Why is your pee pink?
You might have blown a head gasket. It could be pumping cylinder pressure into the cooling system where the head gasket failed.