is my luck really that bad - head gasket

[Darren1983]

TFSI question as usual, sorry people.

my car has loads of 'smoke' coming out of the exhaust especially noticeable when at traffic lights.

Ive read up on it and it says it can be normal for these types of engine, condensation etc..

im worried because every few weeks i need to top up my coolant level?? cant really see a leak anywhere and the waterpump was changed when i got the timing belt done about 3 months ago.

im wondering if it could be the head gasket, again, ive read up on it and it doesnt seem to be a common problem on these engines or am i mistaken?

also there seems to be some splashes of coolant on the engine bay. my mechanic friend did a pressure test on the reservoir and it held good pressure, the cap seems fine aswell, it seals well.

any ideas.

thanks as always
darren

 

[DrEvil]

Well, to state the obvious if you are losing coolant the car is either drinking it through the combustion chamber or leaking it.

Might be worth you doing a leak down test? I got a nice OTC tester from the US as they seemed to have better budget kit than over her, but maybe your mechanic friend has one?

 

[Darren1983]

what does the leak down test involve mate? il ask him.

 

[DrEvil]

You pressurise each cylinder with it at TDC and listen for where it leaks, e.g. if it loses quite a bit of air through the exhaust = exhaust valve leak, bubbles through the coolant tank = head gasket etc. This link summarises it: https://mobiloil.com/en/article/car-maintenance/car-maintenance-archive/how-to-do-a-leakdown-test and you can youtube for a video if it if interested.

 

[Darren1983]

cheers mate, il ask him.

im guessing if it is the head gasket then its going to be VERY costly!

the one thing that does puzzle me is why there is coolant sprayed in the engine bay?

 

[DrEvil]

I agree that it is odd when it has been pressure tested - definitely not a spill on filling up and where about in the engine bay? I've seen some people stick some dye in the coolant (special one that doesn't mess the coolant up) and then UV light the engine bay to try and spot leaks?

 

[Darren1983]

its quattro so the engine in length ways.

it does seem to be around the reservoir, on the right hand side of the engine cover, if you imagine where the pcv is, just in and around that area really.

 

[stu-evans]

I once had a tiny split in a coolant hose that I couldn't trace for ages and sprayed the coolant around the engine bay randomly... Was very difficult to trace, but achieved by manipulating hoses one by one with the engine running until it showed itself!

Doesn't explain the smoke you're seeing... But could that just be condensation given the drop in temps?

 

[carlcall]

its quattro so the engine in length ways..

I think you'll find that all A4 B7's are longitudinal engines irrespective of whether they are 2 or 4 wheel drive.

As it's been said above, it could just be condensation burning out of the exhaust as due to the temps being rather lower the do throw a load more steam out. Even cars that have had a good run can start to throw steam out again if they are stood idling long enough.

If there's no gunk on the filler cap (Not always the case though) and the system isn't over pressurising when the engine is running I would say it sounds like your head gasket is fine, you've also had a new water pump fitted.

If it has only started losing water after having the new water pump fitted I would put it down to one of the hoses settling in and may need the slightest bit of adjustment to tighten it up.

 

[Dan burns]

Same thing happened to my a4 1.9tdi s line a few weeks back. Piles of steam coming out of the exhaust and loosing lots of coolant. Turns out it was my egr cooler leaking water into the intake manifold,also ruined an injector on me. Any way both replaced and problem is gone

 

[Darren1983]

just thought id bring this thread back up as non the wiser really.

still loosing coolant, id say around a litre a month, however it gets below minimum and doesnt seem to drop after that(weird).

i cant see any oil in the coolant tank and no water in the oil. also my mate did a pressure test on the coolant tank and it seemed to hold good.

finally still seeing a lot of white 'smoke/steam'.

 

[Dani_B19]

Have you had a sniff test done in the coolant?

Have to looked around all the coolant hoses to see if there's any dried pink residue?

 

[Darren1983]

the only thing i did see is a bit of fluid(could be coolant) on the top of the subframe on right hand side of engine bay

 

[Dani_B19]

Well you need to do what I've said then take it from there mate.

 

[Darren1983]

Yea I will do mate. Il get a sniff test done. Apparently you can buy so dye to put in the coolant and if it changes to a particular colour then it means that it's contaminated by the exhaust gas's.

 

[Dani_B19]

Yep. You can also buy a UV dye to show up leaks in the engine bay.

Get it sniff tested or dye tested for oil first then take it from there.

 

[Dan burns]

just thought id bring this thread back up as non the wiser really.

still loosing coolant, id say around a litre a month, however it gets below minimum and doesnt seem to drop after that(weird).

i cant see any oil in the coolant tank and no water in the oil. also my mate did a pressure test on the coolant tank and it seemed to hold good.

finally still seeing a lot of white 'smoke/steam'.

. Mate have your egr cooler checked. My car was loosing coolant,oil was fine plus there was no oil in the coolant tank either. Had the car pressure tested and it was grand ,held real good. Ended up getting ****** off and left into to a different mechanic for a 2nd opinion and it turned out the egr cooler had became pourus I.e ******. Put on a new one and it fix the issue

 

[Baka]

I've had two leaks that lost about a litre a month on my mk4 guff.

One was the CTS gasket weeping, the other was a pin hole in a small coolant hose buried in the engine. Both were a sod to find, so hopefully it's something cheaper than the head gasket.