Sneaky McC

Dear All

The Climate Control on our 1996 3.7Ltr Sport only wants to work when the engine is cold or at Motor Way speeds when plenty of cold air is getting to the rads. I'm told that there is likely to be something amiss regarding the compressed gas cooling (a fan thats stopped working). The system is then shutting down rather than become dangerous due to over heating CFC gas. Does this sound credible?

Ta,


Sneaky

silverd2

Is the aux electric radiator fan coming on at idle, when you turn on the AC.
On later model VW's and Audi's (don't know about a '96), if this fan is disabled (fan or fan control unit), the AC will not operate at hot idle...to help save the engine coolant from overheating.
This aux fan (if applicable) should come on immediately with AC turned on, even at freshly started cold idle. I know on 2000 and later VW and Audi (my cars) this is the case.

Sneaky McC

Thankq Silver d2, thats what this guy is saying to me. He is someone local I found on the www. He was the first person to proffer a probable course, everyone else wanted the car in to start testing stuff. He says that the fault should be stored in the fault memory, would that cover the a/c on something of 1996 vintage?

silverd2

Actually wanted to clarify my answer a bit. This fan malfunctioning DOES shut off the AC at hot idle to prevent overheating of the refrigerant,so his advice was correct. BUT it IS a dual purpose fan which also kicks in (regardless of AC) to aid in cooling engine coolant in extreme conditions...hot idle in hot weather. The decision is made, however, by the aux fan control unit which gets it signals from climate control and engine temperature sensors.
I had exactly the symptoms you decribed in one of my cars. I realized that the aux elec fan (side by side w/belt driven fan on radiator) was not running at all...it really should run (at least at low speed) ANYTIME the AC is on in any conditions. I ran 12v directly to the fan (bypassing the control unit)and it worked fine. The fault was with a failed control unit, which I replaced and problem was solved.
In my case, using a basic home OBD scanner (simple handheld unit), no codes showed for this malfunction...BUT, a full featured unit like dealers use may likely read a code(?). The easiest way to start, as I stated, is to check the electric fan at idle with AC turned on...it should be running, when all is normal.
Hope this helps.

Sneaky McC

Fabulous, thats almost exactly what this guy told me...You're not in Ilford Essex (UK) are you? :-)

silverd2

No, I live over on the west side of London, a few miles outside of town...about 4000. I'm easy to find, though...you just go to Canada and take a left

Sneaky McC

:-D

The a/c guy called around late last night. Ran tests, the fan worked. He'll collect the car today and do some work on it.

PaulW

It could be an ignition switch.

Once the ignition switch doesn't reset correctly, the electric fan doesn't work.....check audipages.com ignition switch replacement for details in first paragraph.

Sneaky.....we all went over here:

http://forums.quattroworld.com/a8/

silverd2

Interesting...I'll be curious to hear the final diagnosis.

Sneaky McC

Hi Paul! How you doing Mister, its been a longtime. Yes, I have registered on that other site, it took a while to get the account activated. Then Silver here has been taking good care of me.

Silver, it alls seems to have come to nowt :-/ This guy has now said its the compressor thats the problem... Any ideas for my next move?