A/C question for 1988
Thread Starter
Melting Slicks
Joined: Jun 2000
Posts: 2,923
Likes: 1
From: Las Vegas NV
A/C question for 1988
The car has been park for over a year and half while waiting to be rebuild. Got the car back together last October, now I find that the A/C doesn't blow cool air so I charge it up with 134a freon last night. I converted the A/C sys. to 134a ~ 3 year ago.
Problem:
After charged up with freon, the fan only come on intemmitenly. Should the fan be on all the time when the A/C is on? I changed the high pressure sensor when I converted the sys. to 134a...
What do you guy think? Is it the high pressure sensor again?
Need to have the A/C working to drive to Las Vegas next week:)
Thanks,
Problem:
After charged up with freon, the fan only come on intemmitenly. Should the fan be on all the time when the A/C is on? I changed the high pressure sensor when I converted the sys. to 134a...
What do you guy think? Is it the high pressure sensor again?
Need to have the A/C working to drive to Las Vegas next week:)
Thanks,
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Re: A/C question for 1988 (VQT88Vette)
Normal - Fan switch in on the high pressure line & opens @ about 240psi signalling the ECM to turn on the fan. Fan cools the charge, reducing the pressure. Switch then closes @ 190psi signalling the ECM to turn it off. If the outside air temp is below 50 degrees, the pressure may not get high enough to open the switch until the system has absorbed some heat from the engine. If the outside air is 100, fan may not drop the pressure to the cutoff threshold; hence the fan will continue to run. Disconnecting the switch will cause the fan to run at all times, which is helpful when charging.
