Automotive Air Conditioning Information Forum (Archives)

brady1479 on Thu October 13, 2011 11:42 AM

Year: 1979
Make: Chevrolet
Model: Corvette
Engine Size: 350
Country of Origin: United States

When I slide the A/C control to cold it hesitates in the coldest temp and pushes back to middle. It's almost like it's catching on something or something is in the way. The A/c temp gets really cold if I hold it in the cold temp but as soon as I release it. It goes back to warm. How can I fix this problem.

TRB on Thu October 13, 2011 10:13 PM

Sounds like a cable sticking or door not closing correctly. Going to take some effort to track down which area is causing the issue.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

NickD on Fri October 14, 2011 5:51 AM

Really no such thing as direct AC temperature control, accomplished indirectly by adding heat from the heater core. That can be controlled either with a blend door, or I believe more in 1979 with a heater flow control valve. Not much different than your sink faucet. This was during the transition stage between the heater control valve and the much faster acting blend door. Easy to determine with a quick glance under the hood.

Your problem sounds unique in the sense, these control cables normally seize rather than get loose, but whatever, that is the problem you have to look into. Your vehicle may also have been equipped with automatic climate control, is your temperature control more like a red/blue dial? Those have been around since the early 60's. Back then, servos were used to control the amount of heat functions. Different kind of problems.

What do you have?