cuatrokoop

What type of oil cooler does it have? Some of the liquid-liquid coolers VAG used are known leakers. I had to replace the water to oil cooler on my A4q 1.8t because it was leaking coolant (on the ground). Others have allowed for mixing coolant and oil. My A6q looses some from an o-ring sealed main coolant hose, the o-ring needs replaced. But, if you are going through 2.0L of coolant in 200mi, that is pretty abnormal. Can you smell coolant externally, or at the exhaust tips (burnt coolant has a very specific smell)?

Hate to think that something like a heater core would be bad, I had that problem on an old Rabbit Caddy 1.7L 4spd. Our old Astro had a a coolant line that passed through the intake manifold, which is plastic. It cracked and caused massive leakage. Some out the tailpipe, some on the ground. But I had to carry a couple gallons on me at all times, especially on road trips.

cuatrokoop

I know you aren't, Carlos had mentioned them which is why I replied to his post and not yours, and why I said "...would not have...".

I'm surprised you don't remember my username from our B3/B4 days and realize I know a thing or two about Audis ;-)

carlos50

I really cant tell its leaking, no smells, no dripping, no obvious signs of coolant in the engine bay (looking from the top) and no signs of burnt coolant in the exhaust tips. If it wasn't for the warning light Id have no idea of the problem.

I'm going to check inside my oil cap again, nervous now?

cuatrokoop

You won't see traces on the exhaust tips, you'd smell it when the engine was up to temp and running. Have you pulled the under-body pan off, to see if there is any collected there?

If you pull the cap, and it has a little milky oil on it, it could be coolant, but it may just be moisture that has condensed.

There are ways that a shop can leak-check the coolant system.

Edd W

It is just the normal setup on the 4.2tdi. One coolant rad with the air con condenser and the transmission cooler in the front with an intercooler either side behind the fog lights.

Edd W

A classic fault on virtually all VAG cars at one time or another has been leaking expansion bottles. Lift the bottle up from its mount - just a couple of screws I think, and check the level sensor and pipework from the bottle as well as looking at any seams to see if the bottle itself is leaking.
Have a good look at the rad to see if there are any signs - I know it's not easy to see much of the rad on the V8 but have a good look down with a light to see if you can see an y signs of dried up coolant.

carlos50

Thanks for the suggestion will take a look.

One thought, I fitted new air filters a few weeks ago and it was very tight, had to rip the old ones it, putting a lot of pressure on pushing the housing lids away from the housing to get the new ones in, is there any pipe work around there that I could have damaged or dislodged?

I don't think I did any damage and it all looks ok but not sure what's underneath the air boxes?

carlos50

Update:

I had it tested by a local tech who does a lot of work for our company and he said no obvious sign of a leak was found and pressure was fine.

Today I went on a 5 min run then parked with the front of the car up higher on my parents sloping driveway. When I came out ten mins later the ground was wet, starting from directly below the reservoir where its filled up, so its obviously leaking from there?

Anyone got any pics of likely leaks so I know exactly where to look please?

Thanks

Carl

Edd W

Coolant expansion bottle is an ever lasting archilles heel for Audi- check that and to associated pipework - feed from the bottom and bleed tube from the top.

carlos50

What sort of problem should I be looking for, what are the tell tale signs please?