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Denimblue
17-04-2013, 09:52 PM
Hi,
I've got a 2001 Audi 1.9 tdi with 146,000 on the clock.

Recently while driving up a relatively steep hill, the temperature needle shot up into the red, quickly followed by a red 'coolant' warning on the dash. Before I could stop, the needle returned to it's normal temperature setting and the warning went out.

I stopped and checked the car for any obvious leaks but found nothing and continued the journey without any further problem.

Since then, I've noticed the coolant in the expansion tank dropping to below the minimum setting.

When the car is started and run from cold, the heater fan comes on right away at a high setting and blows cold air, and the temperature needle reaches it's normal setting a lot quicker than normal. The heater doesn't start to blow hot air until the needle is at the normal setting, and on occasion, especially when idling starts to blow cold air even at the hottest heater control setting.

I took it to a garage and the water pump and thermostat were replaced, but unfortunately the problem still persists.

After driving for a while, I've checked under the bonnet and noticed steam and coolant venting from the bottom of the expansion tank when the coolant level is normal.

Any suggestions would be gratefully received.

Thank you.

hibbsy21
23-04-2013, 08:37 PM
Hello mate,

Sounds like a typical head gasket symptom.

Be careful and get it changed soon as you can warp your head.

Rich

Sent from my Nexus 7 using Tapatalk HD

green A8
23-04-2013, 10:29 PM
Had a very similar thing happen to our old B5 TDi. To cut a long story short it was found to be caused by a slightly cracked expansion tank, the mechanic who sorted the problem told me it was something he'd seen quite a lot of across quite a few different VAG models. One thing I would add, I hope you had a genuine Audi thermostat fitted, I've had lots of fun with cheap and cheerful non-OEM ones! A total waste of time.
Hope this helps.

Denimblue
24-04-2013, 08:36 PM
Many thanks for the replies.
It's booked into the garage for next week.
I have removed the expansion tank and given it a good clean as the inside was getting murky orange instead of the pink coolant colour. No apparent cracks or damage. After a long journey when it's up to temperature, the coolant and steam are coming out of the bottom of the tank through the vent.
Fingers crossed and thanks again.