A/C cuts in and out erratically

[Toptech]

Hi everyone. This is my first post on this forum. I'm a ford guy, so don't hold that against me . I'm working on my sons 2002 Sunfire. The a/c compressor will cycle in and out very erratically at times. It may cut in and out every second or two, or it may do it every few seconds. It doesn't do this all the time. Sometimes it works perfectly. The system is fully charged. I believe the problem is electrical. I was thinking it was the low pessure switch but I can't even find one on the car. Does it have one or does it use a temp sensor on the evaporator? Possibly the high pressure switch or the ECM could also be bad. I don't have a manual for this car. Any help would be appreciated.

 

[ericv1984]

Hi everyone. This is my first post on this forum. I'm a ford guy, so don't hold that against me . I'm working on my sons 2002 Sunfire. The a/c compressor will cycle in and out very erratically at times. It may cut in and out every second or two, or it may do it every few seconds. It doesn't do this all the time. Sometimes it works perfectly. The system is fully charged. I believe the problem is electrical. I was thinking it was the low pessure switch but I can't even find one on the car. Does it have one or does it use a temp sensor on the evaporator? Possibly the high pressure switch or the ECM could also be bad. I don't have a manual for this car. Any help would be appreciated.

By temp sensor do you mean the coolant temp sensor? If so, yes it has one, this is what it looks like.... http://tinypic.com/r/1qsw8l/7. Also, the car does have a low pressure switch, but I don't know where it might be located. On the 96 I think it might be on the accumulator, so you might check there to see if it's the same location.

 

[Toptech]

Many cars use a temperature sensor on the evaporator. If it gets to cold it will cycle the compressor off so it doesn't freeze up. Anyway, I have looked everywhere for the low pressure switch and can not find one. Guess I'll keep looking.