AC issues - 84
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,546
Likes: 0
From: Orlando FL
AC issues - 84
Hey guys,
Quick question for the wise. How do I diagnose a possibly failing AC compressor/ clutch. Currently, the car is driving and blowing ice cold air as normal. Occasionally I will get some hesitation at IDLE - Only when the AC clutch engages. I am linking the two together simply because I have no issues when AC is powered off. It sounds/appears as if the clutch might be sticking. Is there a way to test the clutch vs. the compressor?
Thank you,
Kyle
Quick question for the wise. How do I diagnose a possibly failing AC compressor/ clutch. Currently, the car is driving and blowing ice cold air as normal. Occasionally I will get some hesitation at IDLE - Only when the AC clutch engages. I am linking the two together simply because I have no issues when AC is powered off. It sounds/appears as if the clutch might be sticking. Is there a way to test the clutch vs. the compressor?
Thank you,
Kyle
Last edited by quiksilver458; Jul 19, 2006 at 03:56 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Check the air gap between the outer hub and pulley. Should be .020 inch.
Turn the outer hub by hand - should turn over with some resistance, but you should be able to turn it.
Remove the belt and slowly spin the pulley - should be smooth and not catch or make any noise.
Hestitation when the clutch engages may have nothing to do with it. Don't have the ECM PINOUTS for your Year. Something has to tell whatever is controlling idle to step it up when the clutch engages; otherwise it will stall. Need to verify the a/c signal and see what the ECM is doing to step up idle. That's usually done with a scanner.
Turn the outer hub by hand - should turn over with some resistance, but you should be able to turn it.
Remove the belt and slowly spin the pulley - should be smooth and not catch or make any noise.
Hestitation when the clutch engages may have nothing to do with it. Don't have the ECM PINOUTS for your Year. Something has to tell whatever is controlling idle to step it up when the clutch engages; otherwise it will stall. Need to verify the a/c signal and see what the ECM is doing to step up idle. That's usually done with a scanner.
Thread Starter
Melting Slicks
Joined: Apr 2002
Posts: 2,546
Likes: 0
From: Orlando FL
The idle will increase when the clutch engages - initially. The hesitation doesnt happen all the time - it is more intermittent. I do believe the ECM is getting the proper signal to increase idle. I just think the clutch/compressor is holding it back. I will perform the following steps a lil later - have to wait for engine to cool.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Originally Posted by quiksilver458
Hey guys,
Quick question for the wise. How do I diagnose a possibly failing AC compressor/ clutch. Currently, the car is driving and blowing ice cold air as normal. Occasionally I will get some hesitation at IDLE - Only when the AC clutch engages. I am linking the two together simply because I have no issues when AC is powered off. It sounds/appears as if the clutch might be sticking. Is there a way to test the clutch vs. the compressor?
Thank you,
Kyle
Quick question for the wise. How do I diagnose a possibly failing AC compressor/ clutch. Currently, the car is driving and blowing ice cold air as normal. Occasionally I will get some hesitation at IDLE - Only when the AC clutch engages. I am linking the two together simply because I have no issues when AC is powered off. It sounds/appears as if the clutch might be sticking. Is there a way to test the clutch vs. the compressor?
Thank you,
Kyle
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
As designed, a/c clutch engagement should be seamless, though more modern designs actually gets the load signal to the ECM a nano second befor the clutch engages. Everything before about '90 gets it there at the same time the clutch engages. If anything you may sense it, but if it bogs down, something isn't right - signal, worn compressor, overcharged/undercharged, things I previously posted. As sexy as the Vette was in '84, do you really think many would have bought it if it started bucking around just because you turned on the a/c?
