Clunking noise from A/C?
 

I have a weird clunking noise like something hitting something else internally. It is coming from the front of the engine, and it sounds like it is ocming from the A/C compressor. The catch is that the A/C doesn't even have to be on in order for it to happen. I did the long screwdriver "stethoscope" trick and the PS pump sounds fine, the water pump sounds good, as does the alternator. I also checked the idler pulley, and it spins freely without any noise or catching. Also, I get an A/C low pressure "something" DTC.
Is there anything else that I should look at that could be causing the knocking?
If it is the compressor, how hard is it to replace? There are a ton of lines around it, and I'm wondering if anyone has any tips on getting it out.

Does the noise go away with the a/c on? The compressor pulley has a bearing on it that spins when the a/c is off - that could be failing. Pull the belt off and spin the compressor pulley to see how it feels/sounds. Might find the problem.

Don't remember what was required to get it out, but nothing major. From the bottom.

BTW, if you need a compressor, autochainstore reman compressors are pretty cheap (120ish IIRC) but look it over real closely - mine had poor machining at one of the block fitting sealwasher surfaces.

Well, I picked up a compressor Thursday and had it in Friday. I just picked a rebuilt one up at Advance for like $235 with the core. I double checked and made sure that it was in fact the compressor. When I took the belt off, the pulley spun freely, but you could hear the bearings grinding. I put on the new compressor, and not a noise.
Now, when I get it charged, I told them that it needs evacuated and recharged (which they said included the pressure check). The only thing I didn't have an answer for is whether or not it has an orifice tube. It's R134A from the factory, so I don't know if it has one or not.

Nope, the V6 is an Orifice tube a/c system, but your Z28 got the more sophisticated TXV system:


1995 CHEVROLET CAMARO Z28 5.7L 350cid V8 MFI (P) : Heat & Air Conditioning : A/C Expansion Valve

Item Price Core Total
FOUR SEASONS Part # 38804
Block Type O-Ring Expansion Valve

$41.79 $0.00 $41.79
ACDELCO Part # 155461 {#52477944}
VALVE,AUX A/C EVPR THERMAL EXPN w/A/C MAN CONT(C60)

$46.79 $0.00 $46.79

That's good to know. Now, where is the expansion valve located?

It's the aluminum block that the a/c lines bolt to at the plastic hvac housing, in the dash near the heater hoses.

http://info.rockauto.com/getimage/ge...co/15-5461.jpg

You shouldn't need to replace that, though. If the compressor fragged internally and spread debris through the system, then maybe, but a failed clutch bearing should not cause debris in the system.

Why do you ask?

I was thinking that it worked like an orifice tube. They said that the tube wicks moisture out of the system, and that when you have the system open it's a good idea to replace it. I don't know if the expansion valve works the same way or not. The compressor didn't let go, I replaced it because it was starting to make noise, so the expansion valve should be okay then?