Mechanics

POPPING NOISE BECOMES A BIT LOUDER WITH AC ON

1994 Audi 80

Noises problem
1994 Audi 80 4 cyl Front Wheel Drive Manual 118500 miles

Hi, there is a quiet popping noise, you can rather hear it when you are inside, doors and windows closed engine at idle. When accelerating, the popping accelerates as well, to a certain extent, of course. Then the challenge is when you turn on the air condition the noise becomes louder, if the engine is at idle. The car has been looked at by a professional technician, he said the noise comes from inside the compressor, then why you can still hear the noise when the ac is off? There is nothing loose, the ac is operaring normally, but the popping is a bit louder than four months ago. All the belts were changed last week. It does not sound as cam followers, the noise is rather coming from underneath. Help please if you have any idea. Thanks.
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Snob
June 27, 2009.




Hi
The bearing that AC clutch pully rides on is faulty causing slight noise AC off. When AC on the bearing gets loaded and noise gets louder.
Hope this helps
Thanks for donate

Docfixit
Jun 28, 2009.
Thanks for the answer, cool or something! Can you please tell me why this popping noise which gets so loud when I turn the ac on, goes away in one or two minutes, the engine at idle all the time. Maybe the bearing gets more loaded those first minutes as tha ac is establishing the pressure, otherwise I noticed today there is a ac pulley center bolt missing, although I seem to remember it being there before. Could that cause noise? Thanks.

Tiny
Snob
Jun 30, 2009.
Your at the point where removal of clutch assembly for inspection is necessary.
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Docfixit
Jul 1, 2009.
Thanks again, today I passed by the Audi workshop and that was exactly what they told me. Of course the central bolt was in its place. Are there any typical failures of the clutch that coulld cause rattling? My car is 15 years old but it was hardly used before I bought it, the compressor cools perfectly, maybe it is a good idea just to take the belt off till the clutch gets looked at? Is there any source where I could get a closer look at clutch parts, the ETOS thing doesn't go in details into it. Thanks again, if I could find a place to look at the underneath I would rather do it myself as those guys always want you just to buy a new car or something. Cheers!

Tiny
Snob
Jul 1, 2009.
Click on site at bottom of this reply ie. Manuals and for $9.95 you will get Mitchell on demand all the info for entire car and good instruction for AC repair and pics

Docfixit
Jul 1, 2009.
Oops, my car is not on the list. Well, what about clutch failures?
Certainly my case needs closer investigation. Thanks anyway, please keep being helpful: )

Tiny
Snob
Jul 1, 2009.

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