The a/c on my wife's 1999 Cavalier no longer blows cold. This started back in January (yes some of us use our a/c in January...) when it was blowing cold until it suddenly cut off on the freeway. Went from blowing cold to warm just like that; I was in the car when it happened and it seemed like the compressor shut off. It would not come back on until we parked and went inside somewhere for a bit and came back out. I verified that the compressor was turning, but there was no cold air.
My immediate thought was that it was low on freon. I bought one of those recharge kits with the low-side gauge and hooked it up. The pressure on the low side was reading high with the compressor on or off, the system would not charge, and still no cold air.
We left it alone with non-working a/c until now. I finally bought a proper gauge set and these are the readings:
Compressor off: ~70-80 on both low and high side
Compressor on: Low side drops to ~65 and high side slightly over 80
Compressor on/engine revved: Low side ~50, high side ~100
The air gets *slightly* cool when you rev the engine, but not cold. Condenser stays cool to the touch. The compressor clutch engages, compressor runs and changes the pressure slightly, and the radiator fan runs.
A few other things to note: For the past year or so, the air out of the a/c has not been particularly cool at idle, but when the engine is revved/car is moving, it has cooled down to acceptable levels. The compressor makes a noise that's best described as being somewhere between a knock and a rattle at idle (I can't hear it at higher RPMs but maybe the engine just drowns it out) but it did that while the a/c was working too.
My best guess from all of this is that the compressor is simply worn out, and can no longer generate enough compression to effectively cool. Why it would just cut out all the sudden though, I have no idea.
Please, someone tell me I'm wrong here before I go spend money replacing it.
My immediate thought was that it was low on freon. I bought one of those recharge kits with the low-side gauge and hooked it up. The pressure on the low side was reading high with the compressor on or off, the system would not charge, and still no cold air.
We left it alone with non-working a/c until now. I finally bought a proper gauge set and these are the readings:
Compressor off: ~70-80 on both low and high side
Compressor on: Low side drops to ~65 and high side slightly over 80
Compressor on/engine revved: Low side ~50, high side ~100
The air gets *slightly* cool when you rev the engine, but not cold. Condenser stays cool to the touch. The compressor clutch engages, compressor runs and changes the pressure slightly, and the radiator fan runs.
A few other things to note: For the past year or so, the air out of the a/c has not been particularly cool at idle, but when the engine is revved/car is moving, it has cooled down to acceptable levels. The compressor makes a noise that's best described as being somewhere between a knock and a rattle at idle (I can't hear it at higher RPMs but maybe the engine just drowns it out) but it did that while the a/c was working too.
My best guess from all of this is that the compressor is simply worn out, and can no longer generate enough compression to effectively cool. Why it would just cut out all the sudden though, I have no idea.
Please, someone tell me I'm wrong here before I go spend money replacing it.
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