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Im sorry but I have read just about everything I can find about testing the AC compressor and I know what to do but cant seem to find the correct location of the low pressure switch.
Everyone mentions to jump the low pressure switch to see if the compressor engages and I get that but I cant find a pic or video on where exactly that is or how to jump it correctly.
I tested the system and it is low on freon but don't want to just blow $$ into the system without first checking to see if the clutch engages.
I have replaced the entire system on a pontiac LT1 but never had to do it because I knew the compressor was bad.
On my 92 LT1, it is located on the top line that comes out of the evaporator housing. It is tucked up close to the evap housing, you may have to move a wire loom to see it.
I already purchased the freon but why waste it if I need a new compressor?
Most likely your just low. Why do you think the compressor is bad. Why would you want to take a chance breaking the switch or the compressor playing with it?
Well because I have owned the vehicle for only a few days now and the previous owner didn't have any info on it. It doesn't kick on and pressure tested and is very low but still holding pressure. I can move it freely so it isnt locked up.
Just wanted to give a quick check to see if clutch engages before dumping freon into it.
Well because I have owned the vehicle for only a few days now and the previous owner didn't have any info on it. It doesn't kick on and pressure tested and is very low but still holding pressure. I can move it freely so it isnt locked up.
Just wanted to give a quick check to see if clutch engages before dumping freon into it.
Turn it on max ac open the windows and dump a can in. Stop fussing over sevan bucks.
Do you have a refrigerant pressure gauge ??? With the compressor not running, and the car cold, the high side and low side pressures will be equal. You should see at LEAST 50 psi - more typically around 80 psi for a cold static pressure. I'm not sure what pressure the low pressure switch will kill the compressor - but I think it's safe to say if you don't have 50 psi of static pressure you are WAY low on refrigerant.
You might want to google R134 pressures, and spend a few minutes doing some reading.
I appreciate the response but I still dont know what Im looking for? Anyone have a picture of there LT1 94 and a quick how to jumper?
Thanks
Here is a picture of the one on my 92. It is the same as your 94, I just changed it a few weeks ago with one from a 94 because it is used with R134a. Just unplug it and jump the pins together in the pigtail.
Hope this helps,
Here is a picture of the one on my 92. It is the same as your 94, I just changed it a few weeks ago with one from a 94 because it is used with R134a. Just unplug it and jump the pins together in the pigtail.
Hope this helps,
Terry
not to thread highjack, but i am actually missing the switch itself so i jumpered the plug and the ac compressor will only stay on for 30 sec then shut off. the fans stay on. I think this is called the cycling switch correct? shouldnt it keep the compressor on even if jumpered?
I always thought the low pressure switch was mounted on the evaporator exit tube (am I wrong?):
Not wrong, It is hard to see with the wire loom and coolant line in front of it. Mine also points to the engine side. Here is another picture with the lines pulled back out of the way.
Ok so I found the darn thing but couldn't unplug it. I just went ahead and filled with 1 can and no it isnt $7 here in the keys. Advance auto special at $19.99. Anyway compressor kicked on and cold air began to flow.
I do have cool air coming from the location in the pic. Apparently the black putty is no longer there. Is it normal to feel air flow coming from this location? It only does it when ac is turned on so I am confused. If it were a leak wouldn't I feel the same regardless if car was running or not?
Here is the pic any suggestions? The liquid in pic is water that I sprayed. I thought the connector was leaking but it is coming from the opening the red arrow points to.
Last edited by Graphicsplus123; Jul 21, 2015 at 02:41 PM.
Reason: add info
I do have cool air coming from the location in the pic. Apparently the black putty is no longer there. Is it normal to feel air flow coming from this location? It only does it when ac is turned on so I am confused. If it were a leak wouldn't I feel the same regardless if car was running or not?
Air will come out of that hole whenever the HVAC blower is on. It should be sealed with wonderful stuff called "dum dum" by the HVAC folks. It's a black tar-like substance that comes in strips separated by plastic sheets. You mold it around the tubing to seal the hole:
Another AC thread sorry 94 LT1
