Hi all,

I would appreciate some suggestions on an elusive coolant problem. It's on a 97 A4 1.8 20v with aircon and is an auto box. It is using about 3/4 of a litre a week.

I have had the piping checked by 2 mechanics and they can't see any leaks. It's also a low miler and I can't see any oil in the expansion bottle to suggest the inner radiator pipingis leaking/mixing through the cooler etc.

Only thing I can think of is that the heater matrix is leaking,BUT I can't see any of the usual coolant loss that fills the footwell or on the cabin carpet walls!

If it is a matrix do you know if I can buy new seals or is it just a replacement matrix that's needed and where exactly are they situated on this model? Is it a pig to get at?

Any thoughts on this would be greatly appreciated as I'm a little stumped!

Regards


Mak

 

is the car smoking white. it is not common on 1.8s but I have seen a blown headgasket

 

Check you oil and see if there is any discoloration.

To lose that much coolant, and see no signs of leaking anywhere, its almost got to be a headgasket. Look for white smoke as well.

 

I had some experience with this recently, so here are my $0.02:

If you don't have any of the symptoms above, check your coolant flange. Its an elbow shaped tube located at the back of your engine, very near the battery. If you see stains/rust, replace this part.

Otherwise, check the seals of the tubes leading from the coolant expanision tank to your engine. It took me several days to find my leak, and all it took was a new adjustable ring seal at the end of the hose. VoÃ*la, it was fixed.

If you need the part number for the coolant flange. PM me and I'll look for it.

 

so, if their's no sign of a puddle under your car, there's only 2 places it could go. 1. your head gasket is gone and its going into your oil. easy way to check this, open your oil cap and see if there's any of the whitish yellowish coagulated gunk on it, or anywhere you can see inside. next time you're changing your oil pay close attention and see if there's any stuff in there too. the other thing is the heater core, but generally you'd smell coolant when you turned your heat on if that was the case.

 

Many thanks for the advice guys much appreciated. I will try your suggestions over the next few days when I get time. Could someone be a little more specific as to where the coolant flange is located I will check this.

I'm pretty sure it isn't a head gasket as I have only had the car a month and as soon as I bought it I took into a specialist for a full overhaul and service. He told me there may be a coolant problem but ruled out the gasket (and oil is clean I've checked so is the cap) and to keep an eye on the levels.I had to take the car back with me that day so he couldn't have it to deduce further.

Problem was distance. I cannot take it back for him to rectify as it's 800 miles! I have phoned him since and he said he thought it was probably the heater matrix. I'll phone him again with your suggestions. No Audi dealer situated here either.

I can see water dripping after I switch off (but it was night last time) and I didn't know how to tell if it was just the aircon after normal operation. If airconwhicharea will it drip from? Asit was dripping centrally. Ambient temp is around 35 c! Not UK!


Thanks again for the great response, I'll check up with him some moreso I don't waste anyones time!


Mak

 

Here's the link for the Coolant Flange DIY link as well as pics of what it looks like:

http://forums.audiworld.com/a4/msgs/2478357.phtml

This site gives the part numbers:
http://forums.audiworld.com/a4gen2/msgs/1044511.phtml

I had to replace this part on my car too as it was leaking coolant.

Hope this helps.

Kevin

 

Many thanks Kevin I will have a look at this and see if it appears the cause of the problem.


Mak