2003 Pontiac Montana

Air Conditioning problem
2003 Pontiac Montana 6 cyl Front Wheel Drive Automatic 115000 miles

a/c seems to kick in and off at variable rpms and when it kicks off the motor.

I added aprox. 18oz can of freon and it started doing this. It was working fine before but it seemed it wasnt cooling off quick enough.

what should be the average temp in the car at different exterior temps, with the a/c not at max and in " 1" vice max cold position?
July 2, 2010.

Do you have rear air or just front air?Also do you have a pressure gauge on your charging hose?Does your a/c cooling fan working for the a/c condensor?If your a/c was blowing cold before you charged it putting in 18oz's sure is a lot you could be over charged. Your a/c outlet temp with recirculation on blower speed med 2 should be about 50 degree's or less depending on outside temp and humidity.

Jul 2, 2010.

Greatly appreciate your response. Yes I do have rear a/c. Everything works (ed) just fine up until I added that 18 oz. Humidty has been high so I might just be overworried about nothing. However, the kicking in and out is what really concerns me.

I do have a pressure gage and according to the table it was within range (green) before and after it sucked down the 18 oz of freon. It did not seem to have gotten any colder.


Jul 3, 2010.
If your compressor is cycling and it's not cooling down then something is wrong. Is your cooling fan working for the a/c?Also what is your low side pressure?I would also check your high side pressure. That's how you diagnose a/c problem's when the compressor is running what the pressure's are.

Jul 4, 2010.