AC question

[garretb]

My AC had started to take longer and longer to start cooling off, and would only cool when driving. Finally, before I had a chance to take it in, it basically went out altogether. I brought it in to a shop and they evacuated and recharged the system. It's cooling now, but not great. The guy there said that the compressor is going out and that he thinks that it's the evaporator that's leaking. He said that he put in some dye and would be able to tell for sure where the leak was using that. His quote for changing the compressor, evaporator, and expansion valve (or maybe it was the temperature sensor, I don't remember which) is about $1800.

So my questions are:
1) Is it possible to just tell that it's the evaporator is the source of the leak? The evaporator is behind the dash is it not?
2) Is the price quoted about average with this type of job, assuming that what he says needs to be done is correct?
3) Should I have it checked out by someone else?

Thanks,
Garret

[SRR2]

From where I'm sitting, that guy sounds like a crook. It's rather unlikely that all of those parts could have gone south simultaneously. IMO, you'd do yourself a favor by going somewhere else. Maybe even try the dealer.

[MBXB]

He's hosing ya!

My indy charges about $700 for a complete compressor/drier replacement. Which I figure is pretty fair after checking on the best prices for the parts only, and the "Pain in the Ass" installation factor.

[DanDombrowski]

I've found that most people that take their car in for A/C work get told they need to "replace everything", not really as a scam for your money (although they would like it), but as more of a "I don't know where its leaking, and I don't want to waste my time trying to find out."

So, if they replace everything, they can't get it wrong, and don't get hit with a "you replaced the compressor for $700 and that didn't fix it, I want my money back".

The money might be a little high, but the diagnosis isn't really a diagnosis at all. Find where its leaking.

[Blitzkrieg Bob]

when the exchanger is suspect.

If you have ever changed one yourself you'll know why. It is a royal pain in the southern hemisphere.

The compressor, drier, condenser are all pretty striaght foreward jobs

The dye in the system is a great way to find the leaks.

If it is the exchanger, then the dye will start to show up in the condensation water dripping from behind the firewall when you park. It should glow when a black light or if there is a lot of dye then fluorescent light is applied.

[632 Regal]

is do basicly some of the stuff he wants to do. Get another evaporator and replace it if its stained from the dye, check the whole system, maybe you just have a leak at one of the fittings.

I knew a guy that would do the same sort of thing at a shop, he would quote it and sometimes get lucky and the leak was right at the valve. Replace parts, evac and recharge bam...1500 bux.

[pyro]

did you check your heter valves? my firends car had them break and he ended up repplaceing alot of his ac system to find out it dind't do anything. it ended up heter valves were leeking hot coolent into the heter core.

[Kalevera]

Actually, $1800 for a new compressor/evap/charge (and a receiver/drier, can't remember if it was in the list, but it should be) is reasonable. In fact, I'm surprised it's not more -- the OEM compressor is ~ $600 and the OEM evaporator isn't cheap, either. Make sure the shop will use good quality stuff, not cheap ****.

A/C repairs on E34/E32 are *EXPENSIVE* -- people don't seem to realize this. The evaporator should last the term of the car, but replacing it is a labor intensive job, similar to the heater core job (have the shop replace that while they're in there if you go ahead with this).

Adding dye to a non-blatantly leaking system is the first step in diagnosis. If the evaporator is bad, sticking a black light around the trans hump will show the dye leaking from the air box drain holes. Don't let them get it confused with the cosmolene residue (which is probably still there). These systems commonly lunch condensors -- we replace them all the time.

For what it's worth, be sure to read Brett's A/C article. Some info might be useful:

http://www.koalamotorsport.com/article-airconditioning.asp

best, whit

[garretb]

Woo-hoo, moved back from the archives. Now I can reply. :)

So, given that it's a PITA to work on certain aspects of the A/C system, it seems that some are saying that the price I was quoted is not TOO out there. The thing that worries me, though, is that even though this guy told me that he put dye in during the recharge, he's arleady claiming that he's "98% sure" that it's the evaporator that has the leak. So should I maybe take it to another indy shop and see if they can detect the leak using the dye that this guy put in and tell me if it's the evap or something else? If I got the guy who did the original recharge to look at it, would it be possible that I may be able to get him to show me where the leak is and that I would be able to tell if it were the evaporator itself, or just the seals (ie. would it be obvious to me, without any knowledge on A/C systems, that it's a seal vs. the evaporator itself that's leaking)?

Something that I used to notice, when the A/C was actually working, was a very faint hissing sound, like pressure being released, when some component would come on to cool the air. Was that the compressor or evaporator that I was hearing? I don't hear it anymore.

-Garret


Actually, $1800 for a new compressor/evap/charge (and a receiver/drier, can't remember if it was in the list, but it should be) is reasonable. In fact, I'm surprised it's not more -- the OEM compressor is ~ $600 and the OEM evaporator isn't cheap, either. Make sure the shop will use good quality stuff, not cheap ****.

A/C repairs on E34/E32 are *EXPENSIVE* -- people don't seem to realize this. The evaporator should last the term of the car, but replacing it is a labor intensive job, similar to the heater core job (have the shop replace that while they're in there if you go ahead with this).

Adding dye to a non-blatantly leaking system is the first step in diagnosis. If the evaporator is bad, sticking a black light around the trans hump will show the dye leaking from the air box drain holes. Don't let them get it confused with the cosmolene residue (which is probably still there). These systems commonly lunch condensors -- we replace them all the time.

For what it's worth, be sure to read Brett's A/C article. Some info might be useful:

http://www.koalamotorsport.com/article-airconditioning.asp

best, whit