AC went hot in wifes car the other day after being ice cold days before.

bought a 134a kit and did some research here and other places.

ac on max at idle: with guage connected it holds at 50psi, compressor comes on and psi drops to 0, then compressor shuts off after 1 sec, then psi runs back up to 55 and this cycle continues.

i thought my recharge was not enough as I read the pressure reading must be done with the compressor on, i cannot do this as it won't stay on. I've added a tad more freon and idle w/no compressor psi is 55 at 75F ambient.

then i tried shorting the compressor pins with a paper clip, did nothing. then i tried to short the low pressure switch, nothing.

questions:

if i short the low pressure switch (this is on the accumulator right?) i'm shorting the pins on the accumulator and not the 2 wire switch right?

same goes for shorting the compressor, you short the pins on the compressor (this is the clutch?)

I feel i'm close but just can't get the compressor to stay on for a proper reading. i know i have perhaps a leak.

maybe related the car has had a slow oil leak for some months.

TIA!

 

trying to short out the compressor doesn't sound like a good idea to me. you can bypass the low pressure switch with the old paper clip trick, but insert it into the wire connector you pull out of the low pressure switch. you're trying to complete the circuit. don't let your compressor run over a few seconds with the bypass, no need to replace the compressor to find a leak. maybe best to take it to an ac shop if you are unsure what to do.

 

what you do is short the two wire switch wires with a paper clip located on the accumalator.(you can either unplug it and short the wires at the harness or back probe the harness where the wires go in to short the switch.) that should keep the compressor running.
that is the cycling switch. the one on the compressor is the highpressure cutout switch which should be already on since there is low pressure. remember to short the wires and not the actual switch. i have a schematic if still not sure just let me know and ill figure out how to post it. and if you suspect a leak buy r134a with uv additive; it will help you find the leak easier using black light. let me know if n e ?'s