View Full Version : 2000 audi a4 atw pressure in coolant container! !!

02-08-2015, 07:57 AM
hey guys,
My first post here, I got a problem with my 2000 audi a4 with atw gt28rs, its building pressure in coolant container and slightly over heating maybe 10 and stays like that. The weird thing is it happens maybe 2 minutes after running around 10 psi. Is water pump shot? Or water pump belt slipping?

Also noticed that the turbo is boiling the water when engine is off, it sits and boils for about a minute, is that normal for gt28rs?

02-08-2015, 08:33 AM
It sounds like maybe you are creating too much heat under boost like you are leaning right out and cooking the turbo. What is your A/F like under boost> How much boost are you running, what tune, what injectors, any boost leaks? To me it sounds like your EGT's are going through the roof under load and tiyr cooling system is trying to get rid of this heat. I am sure you know better than to hammer on it and then shut the motor off without letting it idle. The turbo boiling water when it is off is also it drawing coolant through it and the heat from the turbo is causing this.

02-08-2015, 11:11 AM
Hey thx so much, I dnt have a a/f gauge, not sure how to check with vcds, and the whole story is, im running eurocustoms k04 386cc file and with running 26psi on the k04 it didnt take long for it to start crying, so im satisfied with the power and tq just wanted more reliability since I use the car alot, and decided to let the gt28rs take the job, hoping to get reliability. And I try to baby the turbo, havent ran more then 10psi on it so far and always let it idle for 5 minutes letting it cool down and after the overheating issue started id keep it idleing and manually pump coolant through the turbo and whatever I can not to damage turbo or engine, so do I get a heavier tune? Or diff tune? I do still have stock rods, could I use lemmiwinks and up the primary feul?

02-08-2015, 11:29 AM
You could try bleeding the coolant first. Might just be trapped air.

02-08-2015, 11:33 AM
Heater works fine, have ran it a week without useing boost and coolant level stays the same, well before it blows it out

02-09-2015, 11:51 AM
90% sure its water pump, im gonna take it off and check

02-09-2015, 11:56 AM
You do know that coolant systems are supposed to be under pressure, right?

If you have pressure, it isn't the waterpump since that is what creates the pressure. I would personally swap out coolant temp sensors and then use vag com to verify the what the coolant temp actually is.

02-09-2015, 04:46 PM
Yes I do know that, vagcom also shows that coolant gets over 105 and the coolant boils over in container, I took water pump off and looks good, still putting new one on tomorrow, and also noticed that the waterpump drive belt is slightly longer than the oem belt I had kicking around so that might be the problem, at idle is there supposed to be a steady stream of coolant going back into the through The top small return hose?

02-09-2015, 05:01 PM
Happened to me with my GT2871R. Turbo got so hot that it would boil the coolant. When I turned the car off, you can actually hear it bubbling from being cooked (resonating in the hard pipe that runs over the IM). When that turbo is on it's way out, you can boost fine. But it will die a slow death as it gets hotter and hotter and hotter. Ask me how I know!

If not the tune (you def need to know what's going on with your system when adding something like that to your vehicle), I would look into that.

02-09-2015, 07:51 PM
I would upgrade your tune and inj. I don't see it creating a problem at that low of boost unless it still has a retarded amount of advance timing. See what I did there..

Are you still running your belt driven fan? My car runs right around 97*-103*c.

What size plumbing are you running? exhaust?

Coolant will keep rising once the car turns off. There is no air moving through the rad to cool it off so it continues to bake.

02-09-2015, 09:56 PM
Yup exactly! I hear the coolant boil in the turbo and which tune do u guys recommend? Hard to believe that a tune causes coolant issues but makes sense, and yes belt driven fan is working and exhaust is 2 1/4in pipe, I was thinking of throwing a inline aux afterrun electric coolant pump, lil like the 99 and up 2.8s have, tht continue to run for a bit after engine is off

02-09-2015, 11:59 PM
Tp, hfc, or stock ? 2.25 will really restrict your exhaust. Member made 30whp by taking off the 2.25 On aN Elim kit.

I'm not saying your tune is the cause but it doesn't help. Could be running leak.

EFK wouldnt hurt either.

02-10-2015, 09:14 AM
Its a 2.25 straight pipe with magflow bottle yup, and good to know!

02-10-2015, 10:57 AM
I would not say it's the tune. I am saying my issue was the turbo itself getting hotter and hotter till one day it just pooped. Might be yours too. Not saying it is, but could be. And when the car is turned off it boils even worse due to no circulation or radiator to cool it down so it basically sits and boils from the chra.

02-10-2015, 12:58 PM
Kay so u think turbo itself is making to much friction? Am I useing wrong oil?

02-10-2015, 01:05 PM
have you even performed a leakdown test?

02-10-2015, 01:21 PM
Nop havent, but I do notice that it doesnt happen at idle, only after driving a bit and feel bubbles surging through the coolant line from the turbo that goes over timing cover

02-10-2015, 01:22 PM
do a leak test. kind of sounds like a head gasket even though it is kind of rare to go out

02-10-2015, 01:54 PM
Log your iats. If it is incredibly high it's your turbo.

02-10-2015, 10:11 PM
Got car put together and same thing, I even put on a oem water pump drive belt and made no difference, so leaves me to believe its head gasket

Could head gasket blow from running too lean?

Iats are very low, exhaust temp is 600c

02-11-2015, 05:32 PM
Stupid thermostat! Took it out and all is fixed!!! Put it in brand new not to long ago, :-/ guess what happens if you go cheap

02-11-2015, 06:37 PM
Good to see you figured it out.

Avant Nate
02-11-2015, 06:50 PM
So your cheap replacement thermostat failed closed? Thus not allowing good enough circulation and cooking it in the turbo? One other thing if someone else has a similar problem, a faulty coolant cap can cause similar boiling issues, as the faulty cap doesn't allow the coolant system to build appropriate pressure, thus boiling over.

Its just odd for it to fail that way.

02-11-2015, 09:04 PM
Yup correct, well in all the over 20 1.8ts Ive fixed ive never seen a thermostat fail closed, they always fail open and yes tht made the water boil and convert to steam in the turbo, << poor turbo

02-11-2015, 09:19 PM
Not all thermostats are fail safe.

I do want clarification on what "take it out" means though. Does that mean you took it out and didn't replace it? Are you running without a tstat?

02-11-2015, 09:28 PM
As of right now yes cuz I wanted it to stop overheating for once! Lol but got the tstat exchanged for a new one so gonna put it in yet, big cons in running no tstat? Besides not getting up to temp as quickly or at all sometimes?

02-11-2015, 09:33 PM
As of right now yes cuz I wanted it to stop overheating for once! Lol but got the tstat exchanged for a new one so gonna put it in yet, big cons in running no tstat? Besides not getting up to temp as quickly or at all sometimes?

One of my biggest pet peeves in life is people who fix symptoms and not the problems. Hell, if I ever run for public office, that sentiment may be my entire platform.

By removing the thermostat, there is no telling if the vehicle is actually "fixed." There could have been an entirely different issue that is now masked by not allowing the coolant to warm up enough in the first place.

Engines run a thermostat for a reason- they need to operate at a specific temperature. By removing the tstat, you are reducing that temperature.

I'm not trying to scold you or anything, just informing

02-11-2015, 09:39 PM
Yeah, I do get what you are sayin, but before I saw no coolant flow whatsoever, not even when up to temp with the tstat in there, no water flow back into coolant container, if I poored water in there it didnt even circulate at all and just the clear water sat there till it over heated and then knew it was a circulating problem, and now without tstat, as soon as I start the small coolant return hose is busy as ever returning coolant which in no time had everything mixed, and yes I do have a coolant freezing point tester and know what im doing when im adding water lol js

02-11-2015, 09:49 PM
The obvious thing to do would be put a new thermostat in there and see what happens. It is an easy procedure on your engine.

On a limb, how does the inside of the radiator look like? And the outside for that matter? Ever blow out the fins? Make sure there isn't a ton of buildup inside?

02-11-2015, 09:57 PM
Rad is like new, nothing blocking anything rad wise and yes ill do that