EGR Cooler Gone?

[amimmortal]

Hi all,

Earlier this year I had a catastrophic EGR valve failure, resulting in a new cylinder head gasket, closely followed by an oil cooler failure.

Since then, I've been monitoring coolant levels and have been alarmed recently at the rate of loss.

So, I had the system pressure tested at the local VAG garage and (thankfully) they've ruled out the gearbox oil cooler, but they are suggesting that the EGR cooler may be faulty.

They've also checked the heater matrix and found no leaks there.

So, they're quoting me 2 hours labour (£196 inc VAT) just to diagnose the fault, which (if necessary) will be followed up by either a replacement EGR cooler (at £300 inc VAT for the part alone) or back at square one, but £196 lighter in the wallet.

Can anyone here suggest any other reason why the coolant is leaking if:

a) The pressure test yielded no external leaks
b) A glycol test in the gearbox has found no coolant in the gearbox
c) The oil cooler, cylinder head gasket (bolts, etc) and EGR valve were all replaced in June (and therefore warrantied)
d) No coolant leaking behind the dash/ into the footwell from the heater matrix.

Is there anywhere else the coolant could be going?

Please help as I need to work out how much this might cost to fix, and whether or not there is some other cause that hasn't been considered yet (that might be cheaper)...

Also, if the EGR cooler is leaking, would that bring water into the engine oil, or would I simply see more oil coming through into the coolant tank?

Thanks in advance!!!
Cheers,

A.

 

[Rick @ Unicorn Motor Dev.]

Hello,

EGR cooler is separate from oil circuit. But, if it is leaking it could make its way into the inlet and could then end up in oil. Are you getting water in oil or not?

You are a long way way but we are able to remove the whole EGR system altogether, meaning no more problems.

Rick

 

[amimmortal]

Hi Rick,

Thanks for the response.

There's no water in the oil, but there is residual oil in the expansion tank from the failed oil cooler earlier this year. Yesterday morning I started the car up from cold and watched a steady stream of white smoke coming from the exhuast for a good 5-10 minutes. This after having the coolant topped up to maximum the previous day, followed by a 40 mile round trip to Kirkcaldy and back.

I'm a little worried about any potential damage this can cause to the EGR itself, which was only replaced 3 months ago. I don't imagine any damage caused by a failed cooler would be covered under warranty...

I'm taking the car to Star Performance in Kirkcaldy, who normally look after my car, but thanks for the offer. I'll keep you in mind if I have any problems next time I'm driving down south!

Cheers,

A.

 

[Paul_TDi]

I had my heater matrix replaced in my MK4 golf, i think it was leaking from a drain at the back of the engine bay, poking out from the fire wall there's a cut out in the sound deadening.

 

[VTEChnician]

Did you get any results?
My EGR Intercooler leaked coolant into the inlet tract, which then just ends up being vapourised in the cylinders and exits the exhaust as water vapour. The leak rate was about 1/4 litre in per 250miles, so there were no visible signs except for the header tank level dropping. Leaks in this component can cause knock-on effects such as damage to the EGR valve and solid deposits into the inlet.
Unless you are certain about your pressure test result, I would advise taking your motor somewhere where they will pressurise your system whilst hot and leave it overnight. If the pressure drops, then get them to put a camera down the EGR tract and look for signs of coolant. Audi dealer should have all the kit to do this, & charge around £75.

 

[sktan]

You might just have to replace a new egr kit.