Intermittent A/C Problems

[xtremerevolution]

I want to get this crap resolved once and for all.

 

Last year I had a specific problem going on with my A/C. It just wouldn't work, so I took apart the piping, replaced all of the seals and gaskets, replaced the orifice tube, and put it back together. It worked...for 2 months. Then it stopped working again. I discovered that if I pressed the A/C compressor relay in a certain angle, it would work, so I wedged something in there to keep it at an angle until I could find a new relay. That didn't seem to solve the problem either, as I now have two extra relays and neither of them work. I didn't get it fixed and fall came around.

 

This year, the system was empty altogether. I discovered one large fitting right before the accumulator had gotten loose somehow, so I tightened it nicely, filled up the system, and I had A/C for about a week, then it stopped working again.

 

Last night I was driving home, I turned the A/C on, and it blasted ice cold air. Perfect. Today, its a little warmer, I start the car, drive for 3 minutes, and try to turn the A/C on, and get nothing. I pull into the McDonald's parking lot for lunch, go over a bump on the onramp, and the A/C kicks on ice cold and perfect...for about 2 minutes. Once I get to the drive-thru microphone and the car's sitting still, the A/C kicks off again.

 

When I turn on the A/C, the engine revs a bit higher, presumably expecting the extra load from the compressor kicking in. However, the compressor never kicks in. It just sits there. I'm thinking it has something to do with that relay or the wiring around that relay. The first time I fixed it this year, it wouldn't kick on till I pushed that relay at an angle and left it there. Now, that doesn't do a damn thing. Any ideas as to how I can test if it is the relay or the wiring? Are there any wires I can short out to simulate what the relay is doing to try to force the compressor to come on?

[White93z34]

i would probably pull apart the under hood fuse block and depin the connectors for the AC compressor relay, clean make sure they get a tight connection to the relay and coat in dielectric.

[xtremerevolution]

Alright, I'll start there first and let you guys know how it goes. Thanks.

[White93z34]

also one issue I noticed last year on Shaun's GP was that the ac compressor clutch was faulty. it would try to engage it, but unless you hit the compressor clutch with something or rev the engine up it would not engage.

[xtremerevolution]

lol. I should carry a hammer with me in my trunk at all times for that purpose!

[WhatTheFehl]

I don't know if this will help but something I noticed in my uncle's '04 Cavalier. For a while I was driving it regularly. Anyway, the A/C worked nice and cold but I noticed that it would shut itself off in stop and go traffic, if you stopped for longer than a few seconds it would start to get warm. Ended up being a bad cooling fan relay. The bad relay caused the aux. fan to not kick on in traffic like it should, and because of that the A/C shut itself off as a fail-safe. Replacing the cooling fan relay resolved this. Moral of the story: check your relays!

[xtremerevolution]

The cooling fan relay works. Thanks though.

[xtremerevolution]

You know what sucks? A/C has worked perfectly since I created this thread. Every single time.

 

Watch, it will stop working on the first day temperatures go up into the 80's.

[Crazy K]

It must be a fuse box issue. Pull ALL the relays and look for corrosion on the tabs. next unhook the box and flip it over and look for damage to any of the wires for the relay. I bet one wire it loose and ready to separate.

 

 

ALSO>>>> I coat underhood connectors, including those in the fuse box, with dielectric grease as it is a safe inert lubricant intended for such purpose. You should do the same.