Greetings,

Toward the end of last summer, My AC started to act up. Here is the sequence.

I have not noticed it on cold days (fall /winter), but I wasn't paying attention either.

On a warm day -today-(65+ deg) I start my commute, and I turn the AC on. Doesn't matter what fan speed or which outlets (max or norm etc). Blows cold and acts normal. Compressor cycles on and off as it should. After about four miles, (the same place each time), The AC will only blow "ambient air". The compressor will not start cycling again until I shut the car off for an hour or so. Then I can restart the car and duplicate the same issue. It happens consistantly.

Based on my symptoms I am suspecting the high pressure cut out sw.


Anyone have any other thoughts or suggestions for this one? Thanks..

Paul.../NH

Given what you describe I would suspect low freon causing the low pressure switch at the receiver dryer to cut current from the clutch of the A/C. Too much freon would shut the switch off at the high pressure end of it. You need to take it someplace and have them put the gauges on your A/C system to determine just exactly what is going on. Today's air conditioning systems only carry 1 1/2 to 2 lbs of freon so without gauges it would be really easy to get too much in there.

Davescort97, Tnx for the info and reply. I looked at the status of the R-134a charge today. it was a little low. I brought it back up to spec per the instructions on the recharge kit. It blew a lot colder than before (though temp has never been an issue), However, it did behave the same way as before. It would cycle on for a few miles, then no compressor. If I shut the AC off for about 10 minutes (and still keep driving), when i go to turn the AC on again it will blow cold and the compressor will come on. Then after a few minutes, off again. No cycling. This time I turned it back on while I was entering my driveway. i left the car running for 20 minutes with the AC on medium, and the compressor cycled normally for the whole 20 mins. Then I took it out on the road for an 8 mile trip. The compressor shut off after about a mile. Would not come back on until I turned the AC off at the panel for 10 or so more minutes. Repeat etc. Does this give you (or anyone) any further info that might help me with the diagnosis?

Thanks

Paul.../NH

I'm sorry I don't much helpful input, but. Mine is 99 model doing the exact same thing. Only, I've noticed it's intermittency seems to be based off temperature (outside temp). I had a road trip in the heat of the day. It would work fine for about 6-8 minutes then the A/C clutch will no longer engage. I shut off the A/C for 10 minutes or so, turn it back on and it works. Then, again in 6-8 minutes is stops working ... so on and so forth. As the day cooled, it would work for 15 minutes before failing, then 20, then 25, ... as the sun set it worked fine for the remainder of the trip (about an 1hr). I'm not for sure, but I think I noticed that when the A/C clutch would engage it would take a bigger bite out of the engine power during the hotter portion of the day, which makes me wonder if it's the start of a overloaded/failing compressor.
I'm curious if you've being able to figure the issue out yet or not.

Thanks,
Jerrold