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My car started making clunking/knocking noises when I turned on the AC or the defroster.

I took it to a shop, and they said that the compressor was going out, so they would replace the complete system for ~$1000 (both parts and labor included)

Is this what's going on and the best solution to remedy it?
My car is only worth like 2k, but its the only car in my family i can drive, and my parents think that come winter I am going to need to defroster (I live in the bay area near SF, CA).
The car sits outside on the curb during the night (all of our cars do)

It is a 92 legacy LS N/A AT FWD with 162k on it.

Thanks

That's probably it, yes. When compressors go bad they start to knock. It's not really good for it, but you can try popping the hood and getting a friend to turn on the air conditioning so you can locate the knocking sound. It should be pretty clear if it's coming from the A/C compressor.

You can disable the A/C system by pulling out the four black relays from the underhood fuse box. Then you'll be able to use the defroster without having the compressor run. It'll be less effective, but as long as you use the heater in conjunction with the defroster it will function.

You definitely don't need to spend a thousand dollars even if you do want to fix the A/C. You can just pick up a used compressor for less than a hundred dollars (make sure you match the type on your car -- can you look at your compressor and determine whether it's a Zexel or a Calsonic?) and a new aftermarket receiver-drier for like $50, a pair of R-134a retrofit fittings for maybe $10 or $20, and some refrigerant and oil for maybe $15 or $20. Then you just need to remove the compressor and receiver-drier, flush the system, install the replacement parts, evacuate the system, and charge the system with oil and refrigerant.

You can do the last few parts yourself if you buy a manifold gauge set, build a vacuum pump out of two used refrigerator compressors and some fittings, and adapt brake cleaner to use as a flush. Or you could have a shop do it for probably no more than an hour's labor.

I'd just run the thing until it dies. My old compressor knocked for quite some time, and it really never died on me either. Go figure, but the one I put in to replace it died....

But a knocking compressor is probably sending little flecks of metal out into the rest of the system... it might be the reason your replacement died, in fact.

The "black death" phenomenon is most prominent on certain Ford models, but any time a compressor is insufficiently lubricated it can start doing something like this:

http://www.ackits.com/index.cfm?fuseact ... ck%20death

That's why I suggest the flush, and why I suggest pulling the relays or fixing the system.

ok vrg3, ill check the A/C brand on the weekend and i may just follow your steps for removing the relays for now

btw, where could i pick up those extra parts like the reciver-drier, retrofits for R134a, and the oil?

noob question though, where's the fuse box? (i haven't taken a detailed look under the hood)

yes, im very new to this

Thanks

You can get a receiver-drier at an auto parts store... There are third-party ones that are fairly cheap.

R-134a refrigerant, retrofit fittings, and refrigerant oil are also commonly found at auto parts stores.

The fuse box is on the driver side, next to the washer tank.