Any GM air conditioner experts out there?
99 GMC Sierra 2500 (99-2006 BODY STYLE)
AC works and then stops blowing cold air. Compressor is cycling off.
1) You can turn of the AC and continue to drive a few miles and then turn it back on it will start working. Turning it on immediately will not.
2) Another 3-10 minutes it will stop again.
Air flow seems to slow down slightly. Running the blower at the highest level will make it run longer.
3) Higher humidity seems to make it last less.
4) Outside air lasts less than recirculation mode.
5) Split between air intake and discharge is usually 40 degrees or more.
6) Driving a constant speed 95 degree ambient air outside I can easily see low 40s on at the discharge.
7) Cabin air filters have been changed.
8) System has been checked once (was told it was a couple ounces low). Took it back as it was doing the exact same thing when I left. They discharged the system, pulled vacuum , and recharged. Still the same.
I think the evaporator is freezing up but why? Low refrigerant and they missed it twice?
I may have to dig out my gauges and take a look at the pressures.
Anyone have any ideas?
99 GMC Sierra 2500 (99-2006 BODY STYLE)
AC works and then stops blowing cold air. Compressor is cycling off.
1) You can turn of the AC and continue to drive a few miles and then turn it back on it will start working. Turning it on immediately will not.
2) Another 3-10 minutes it will stop again.
Air flow seems to slow down slightly. Running the blower at the highest level will make it run longer.
3) Higher humidity seems to make it last less.
4) Outside air lasts less than recirculation mode.
5) Split between air intake and discharge is usually 40 degrees or more.
6) Driving a constant speed 95 degree ambient air outside I can easily see low 40s on at the discharge.
7) Cabin air filters have been changed.
8) System has been checked once (was told it was a couple ounces low). Took it back as it was doing the exact same thing when I left. They discharged the system, pulled vacuum , and recharged. Still the same.
I think the evaporator is freezing up but why? Low refrigerant and they missed it twice?
I may have to dig out my gauges and take a look at the pressures.
Anyone have any ideas?