miho35o

Whenever i move the mode select lever for the climate control system on my '76 98 to Off, the heater stays on. Whenever i switch it to one of the other functions, like Vent or the A/C, it operates fine. The temperature lever works fine, it's just when I switch the system Off, there is always air coming out of the floor vents. My guess is that one of the control arms behind the dash is stuck. Anyone heard of this and is it a hard fix?

Olds64

I've never heard of that particular problem. You might want to check for a vacuum leak under the dash. Most of the air doors back then were vacuum operated. Perhaps one of the vacuum lines worked loose or dry rotted.

joe_padavano

When you say it won't turn off, do you mean that you can hear the fan motor running or just that air keeps coming out of the vent? If the latter, I suspect that either one of the vacuum hoses has come loose or one of the vacuum actuators has gone bad.

rocketraider

Default position on loss of vacuum is floor vents. If the car is moving you'll have airflow thru them even with system turned OFF and blower stopped. Not a problem as long as it switches to the other vents as designed when they're selected. If it bothers you, start checking for cracked or rotten vacuum lines or a leaking vacuum storage ball underhood.

Keep in mind that a Tempmatic (assuming you have it since you call it climate control) doesn't operate quite like a C.A.C. system does. Either operates more reliably than a Comfortron.

miho35o

i was looking under the car last night and i noticed a small hose about 1/4" in diameter hanging down. i have not worked with vacuum hoses before - i had them replaced at the garage. this one looked new. could that be the hose that might have come loose?

rocketraider

Straight from the 1976 CSM:

Custom & Tempmatic AC Functional Tests

Control Setting: OFF

System should operate as follows: Air should be delivered out of the heater outlets at low speed only. Temperature may be regulated by the lower control lever.


No need to chase a problem that isn't there. My 1976 Regency w/ Tempmatic and 1974 Hurst w/ C.A.C. operate like this, as did every other 1974-76 Olds I've owned.

miho35o

i guess i just never noticed it. Up to now i have really only run the vent and a/c and when they were off, i had the window open. Some cars have a little airflow coming from the dash vents when the system was off but not from the floor. Is that specific for the Tempmatic system?

BILL DEMMER

this was a safety feature to keep some fresh air flowing into the cabin at all times.


bill