Mazda 2007 cx9
When I get in my car in the morning the A/C works fine.I will make 2 or 3 shopping stops and after the third stop the a/c blows hot air.the system has the correct freon charge.my car has 202000 miles but I maintain it very well.What could be wrong?Many thanks
the system has the correct freon charge
How do you know? Has it been evacuated and recharged with the correct amount of refrigerant by weight recently? Otherwise it's pretty likely that some has leaked out over the last 17 years. Is the compressor clutch engaging when the AC is discharging hot air?
The guy at the auto parts store put a gauge on it and said that the freon was ok. He did say that the compressor was (cycling?) a couple of times a minute and maybe I need a new compressor but he could not tell for sure.Thanks for your response
Thank you so much! Now I will find a mechanic!
Try to find a good independent shop. Stay away from chains like Pep Boys, Midas, etc. and dealers.
The guy at the auto parts store put a gauge on it and said that the freon was ok.
Guys at auto parts stores are not mechanics. You cannot tell the refrigerant level with a gauge. (He probably even used one of those useless recharge kit low-side gauges they sell at parts stores, not even a full gauge set.)
So at this point it is unknown how much refrigerant is in the AC system.
He did say that the compressor was (cycling?) a couple of times a minute and maybe I need a new compressor
A new compressor? Rapid compressor cycling is a common symptom of low refrigerant. Don't take mechanical advice from auto parts store clerks.