hairbear21

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.

JP95ZM6

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.

hairbear21

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.

JP95ZM6

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

hairbear21

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

JP95ZM6

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



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?

hairbear21

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?