air conditioner fails in extreme heat

[bluesuby]

With record high temperature here I have been dealing with a/c that won't blow cold when the outside temp gets up around 98 to 100 degrees. Things are ok when the temperature is lower, even by a couple degrees. I did notice the compressor is not cycling when this event happens. Any ideas for a fix? The system is fully charged, and several months ago I thought the compressor was reluctant to turn over. That was fixed by replacing the harmonic balancer which was pretty well shot after 181,000 miles.

[08SpecB_DE]

Do you know the pressure values? Does it get colder as you drive down the road but get warmer at red lights?

[bluesuby]

Do you know the pressure values? Does it get colder as you drive down the road but get warmer at red lights?

 

I don't know the pressure values. If you are referring to the charge it was checked at a shop. Running at speed has no effect on the cooling. The engine temp stays in the acceptable range.

[08SpecB_DE]

Try spraying the condenser with a garden hose to see if it helps cool the air. It's hard to say what the issue is without seeing the pressures. There could be a slight clog in the condenser or a sticky expansion valve. The compressor could also be getting too hot causing it to cut out. When you are experiencing the issue of the ac clutch not running, check for power on the wire going to the compressor. If it has power, the compressor clutch is going bad. Does the clutch short cycle when the ac is functioning properly? By short cycle, I mean run for a max of 5 seconds then shut off, etc or does it run for much longer?