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Audi A4 air conditioning problem

Hi guys, looking for some expertise here.

Last summer, driving my 2003 Audi A4, my A/C suddenly stopped working, and the “econ” button couldn’t be switched off. I took it to my mechanic, who said that a loose screw had blown a hole through my A/C compressor (image attached). Not only was my A/C not working, but I had to pay $1400 right then and there to get a new compressor installed. As I understand it, the compressor in my car is run by the timing belt and if it jammed, it could ruin the engine. So I paid up, but still didn’t get have the A/C fixed.

My mechanic told me that the hole blown through the compressor had sent shards of aluminum throughout the A/C system. So to fix the A/C, he’d have to flush the whole system and replace parts throughout the car… probably adding up to north of $3,000. Definitely not worth it, considering the total value of the car.

Any second opinions? Is there an easier way to flush the A/C system? As far as I understand, with my new compressor, all the parts of my A/C system work fine, but I just gotta get all the aluminum shards out.

Any help is much appreciated!
Boston, MA

So you had a new compressor installed but didn’t replace the other AC parts? No, there’s no other way to get all the shards out other than doing what your mechanic said and replacing the other parts.

Yeah – I had the new compressor installed just so I could drive it off the lot! So replacing all the other A/C parts and flushing the system really will cost $3,000? Bummer…

+1 to jesmed’s advice.

And, just to correct a misconception, the a/c compressor is run by a serpentine belt, not by the timing belt. If the compressor jammed, it would tear-up the serpentine belt–and likely strand you on the side of the road–but it wouldn’t have ruined the engine. The serpentine belt drives several devices, including the alternator, the a/c compressor, and (possibly) a power steering pump, and when this belt snaps, you are not going to be able to drive very far or very long, but it wouldn’t ruin your engine.

Does that engine actually have a timing belt?
I would suggest that the OP check his maintenance schedule right away in order to see if it lists replacing the timing belt (which can also be referred to as a “cam belt”). If this engine has a timing belt, the interval for changing it was at least 3 years ago, and a snapped timing belt will cause an incredible amount of very expensive internal engine damage.

If there is no listing in the maintenance schedule for timing belt replacement, then his engine is equipped with a timing chain, which typically lasts for ~200k miles before it begins making noise and needing replacement.

The compressor is not driven by the timing belt, but is driven by the single serpentine belt that also runs other accessories. That is a catastrophic failure and a system flush is required to do a proper repair. But, unless the pulley bearing was making noise or showing other signs of failure, a simple disconnect of the magnetic clutch on the front of the compressor should have been enough to get you on your way. Now, you have a new compressor installed, but is it connected? It was a year ago, and if the compressor was installed to a contaminated system, the contamination can migrate into the compressor. If not, how did he seal the compressor? If no sealing happened, I’d be worried about dirt and crud getting in. I just don’t like your options trying to get the A/C working again.

I’d take it to another shop for a second opinion. Replacing the receiver/dryer and expansion valve plus flushing everything else may be all you need.

A loose screw did not blow that hole through the compressor. It likely blew because of a lack of refrigerant oil. That lack of oil can be normal as an A/C system will lose some oil over time as some of the refrigerant leaks out.

The only way I can see this as salvageable would be if the new compressor has not been energized as activating the compressor would force debris into the compressor and the compressor lifespan may be seriously shortened.

If the compressor has not been energized then a thorough flushing and dryer/accumulator replacement may be all that is needed. Knock on wood.

Hi everyone, thanks so much for your help! A testament to the Tappet Brothers and their legacy…

To clarify…

  • Yes, I meant the serpentine belt! Thanks for the correction.
  • I replaced the timing belt and water pump at around 85k miles (car currently has ~115k)
  • When my A/C first stopped working last summer, I was told I had to replace the compressor with a new one in order to not cause more damage. I’d guess that my mechanic didn’t connect it to the rest of the A/C system.

Sounds like I need to take the car to another mechanic for a second opinion. Hopefully it’s just a simple matter of flushing the system and replacing some parts. But my mechanic lead me to believe that it’d be a very intensive, very expensive thing to do.

If anyone has any more thoughts to give me, I’d appreciate them! If not, thanks for the help, and off to another mechanic.

If your car came to me with that compressor, I would give you 2 choices:

  1. Install a compressor just to be able to run the serpentine belt, and you’d have no A/C.

  2. Install a compressor, but to make the system functional replace the condenser, receiver/drier, expansion valve, and flush the remaining lines and components. Then evacuate and recharge the system and test to verify proper cooling fan operation.

#2 could easily go over $2000.

You need the compressor pulley in place to route the serp belt so other things work, like alternator. U paid 1400 for a very expensive belt tensioner basically. Mechanic could have got a $300 used compressor instead. Since it also did not have to be charged with freon. Why not go back and tell him to do it? And get a refund on your unused, NEW compressor?

Please keep us updated. This will be useful info.

I suggest you to go for changing the compressor. Also have a look over radiator, if it needs replacement. You can also check