Chevy & GMC Vans

I really enjoy working on my vehicles when they need something done, and I can do just about anything, but when it comes to the air conditioning and its components I'm clueless. What I do know is that when the air is turned on you should hear the compreasor kick on. Well, I'm not. The air blows, but definitely not cold.

Is my compressor definitely bad? Is there in in-line fuse I could check? Any other possible (hopefully) easy fix I could check? If I have to take it to a shop to check it out, I'll do just that. Just wondering if there's any way I could check it myself.

Any help would be greatly appreciated. It's damn hot down here.

Well, I just did a search through the threads again, and it seems my problem could be due to a low charge. Guess I missed it when I searched earlier.
Could this be my problem? Could I be this lucky? I hope so.

What you can do to verify the compressor is actually not engaging is watch it with the engine running. Then have someone turn the ac on and you should hear a loud click and see the compressor start to turn. If it is not turning on, you could have a bad switch, bad fuse, faulty wiring, faulty compressor or a low charge. The first thing I would check would be to make sure you have 12 volts and a solid ground at the connector on the compressor with the switch on and the ignition on. (This part would be checked with the engine off, of course.) If the voltage is good here, your compressor is toast. If you don't have 12 volts I'd check the fuse next. Then move to the switch and so on. If you can't find a problem with the circuit it may just be low on refrigerant and you'll probably need professional help to diagnose that.

Keep us posted with what you find.

Hi It could be low charge but it would have to be real low as when it is just slightly low the compressor kicks in and out at a fast pace. Every few seconds.
allegro

With the air running, feel the lines going in and out of the evaporator core. Should be cold coming out as well as going in. You've probably are just low and need to charge up from a leak. But it could be something else too, really you need to put gauges on it to see what the pressures are.

Scott

Thanks guys. I'll check a couple things mentioned, also I'll try to get my hands on some gauges this weekend.

Your compressor may not necessarily be bad, so find out if you have power and ground to it and get back to us.

I don't know what year your van is but GM products in general will have the low pressure cut out switch located on the accumulator. The accumulator is the silver cylinder located behind the coolant overflow tank on the passenger side under the hood. Remove the connector to the switch. With the ign. switch on and the AC switch on, jumper this connecter. You should hear the clutch cycle as you jumper this connector. If this works then you are probably low on refridgerant and you didn't even have to buy, beg, borrow, or steal some gauges.
Harv

Thanks TheHarv.
I was actually just getting on to ask just how to "jump" the switch your referring to, then I saw your post.

So do I unplug the connection, and run a short wire from one side to the other? Where the plug would be normally be?

EDIT: BTW its a 2000 Astro.

Vanutty wrote:Thanks TheHarv.
I was actually just getting on to ask just how to "jump" the switch your referring to, then I saw your post.

So do I unplug the connection, and run a short wire from one side to the other? Where the plug would be normally be?

EDIT: BTW its a 2000 Astro.

yep , that will do it

Thanks.

Hey guys, I was having a tiny very small leak on my AC system. My stupid friend (will never touch my van again, said he can check it out). He said I need to get the old 134a sucked out and refilled with new one. No problem and it will be all good, he'll use a 134a stop leak and a another can of subzero to finished it off.

The idiot take a small screw driver and press the canister that holds the 134a and let all the gas out before I even come to see what he's doing. I stop him right away, as all of the 134a was out already.

Now the AC Compressor will not turn/kick in when I put it on Max AC... I guess the above post take care of that, low pressure will not make it turn.

I know I have a small leak somewhere, will the 134a stop leak fix it, is it worth a shot?

Sorry to hijack your thread, I just though it might help as we both have the same issue here (seems like)

Thanks
Mike

The stop leak isnt going to fix your leak, probably just gum up the system at best. If you have a leak, you have to fix it properly. Is the bottom of your compressor covered in oil? Typically this is a common leak point, but it could be anywhere. The big line going to the back on the driver side of the motor will rub through if its the older style line (meaning it hasnt been replaced yet). If you have a UV light you could detect the leak, I think by 97 the van came with dye from the factory. If not, you need to charge it back up and let it run.

To charge it back up, you need a vacuum pump and gauges. Vacuum it out for an hour and make sure it stays as close to 29.92 inches of vacuum, although since you do have a leak it wont. But you will be able to see just how bad the leak is. If it stays in the same spot on the gauge for 15 minutes, its not a huge leak. Charge it up with 134a and a 1/4 of dye, let her run for half a hour and then run the light over all the lines, and components and you should see your leak glow!

Scott

OK, I'll do that, does anyone have a diagram of the AC Vaccume system lines, where they run. Also how do I access it, do I have to take off the engine cover from inside the van, are they lines below the van?

Where can I purchase those lines if they are leaking, are they expensive?

Thanks
mike

You don't need a diagram...just follow the lines and hoses inspecting them along the way. You will need to remove the doghouse to see one of the lines running over top of the motor.