A/C not working
blk95lumina
09-02-2009, 01:26 PM
Hello,
I have a '95 Lumina 3.1L w/ ~150K mi.
When I turn on my A/C the compressor does not even try to engage nor do any of the engine fans turn on at the temp. at which they normally turn on when the A/C is on.
The 134a pressure is low...it measured 40psi at 95F. I figured this is at least enough for the compressor to engage but I could be wrong....not sure what the low pressure switch cutoff pressure is.
I suspect the A/C relay under the hood.
Is the A/C not turning on along w/ the fans not turning on a sure sign the relay is a good place to start or should I focus somewhere else?
Is the A/C relay failure a common issue w/ these cars?
Thanks.
I have a '95 Lumina 3.1L w/ ~150K mi.
When I turn on my A/C the compressor does not even try to engage nor do any of the engine fans turn on at the temp. at which they normally turn on when the A/C is on.
The 134a pressure is low...it measured 40psi at 95F. I figured this is at least enough for the compressor to engage but I could be wrong....not sure what the low pressure switch cutoff pressure is.
I suspect the A/C relay under the hood.
Is the A/C not turning on along w/ the fans not turning on a sure sign the relay is a good place to start or should I focus somewhere else?
Is the A/C relay failure a common issue w/ these cars?
Thanks.
jeffcoslacker
09-02-2009, 06:38 PM
My '97 wouldn't do anything this year after working fine since new. Static pressure, like yours, seemed enough to allow operation but before chasing demons I tried a charge...soon as I pulled the trigger on the cheapo suicide tap the system came on, and one can was enough for it to work perfect.
jeffcoslacker
09-02-2009, 06:40 PM
PS I swapped the A/C relay and one next to it, fuel pump relay, to eliminate that as the cause before I tried charging...you could try this.
If the relay is bad, your car won't run with them swapped
If the relay is bad, your car won't run with them swapped
brcidd
09-02-2009, 08:05 PM
Takes 47 psi to turn on a/c--- your system is drastically undercharged- due to a leak-- most likely location--- compressor shaft seal and/or body o-rings
blk95lumina
09-02-2009, 09:03 PM
Thanks for the help. I'll try both ideas just to be safe.
The compressor is in fact leaking and has been for at least the past 6 months that I know of. It must be the shaft b/c the pulley is slinging oil all over the place under the hood.
Is there anything worth doing to fix the shaft leak or is a new compressor the only answer?
Any idea how long I have before it just dies or seizes up?...assuming I get it going again.
Thanks.
The compressor is in fact leaking and has been for at least the past 6 months that I know of. It must be the shaft b/c the pulley is slinging oil all over the place under the hood.
Is there anything worth doing to fix the shaft leak or is a new compressor the only answer?
Any idea how long I have before it just dies or seizes up?...assuming I get it going again.
Thanks.
brcidd
09-03-2009, 07:43 AM
I reseal those compressors- a new shaft seal and new o-rings- and a sealing surface clean-up will fix it right up-- but most DIYs don't have the tools to open up the compressors....there is plenty of info on the web on how to do it- just look if you are interesting in saving 3 or 400 dollars...
blk95lumina
09-03-2009, 09:06 PM
Today I added 24oz. of R134a and the compressor and fans kicked on almost immediately when I began filling it. The 2 cans got it up to 40psi at 90F, so it is still a little low but cools OK...I'll probably add just under another can. System holds 2lb., so it must have been completely empty.
I'll see what I can find online and if I am up to it. If not, looks like Rock Auto sells some Reman. V-5 compressors for ~$230+shipping.
Thanks.
I'll see what I can find online and if I am up to it. If not, looks like Rock Auto sells some Reman. V-5 compressors for ~$230+shipping.
Thanks.
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