Heater only works when set to 85*

[RazoE]

Hey guys, I have this weird issue with my 89's heater..

If I set the temperature to anything below 85, I get room-temperature-like air..

it can be at 76, or 84, and it'll feel the same. The second I go up to 85, I finally feel the heat, however it's super-hot...

I don't mind the super-hot actually, as I drive to work at 6am and sometimes the cars have ice on them:aigo:..

I'm just wondering what could cause this?

 

[supra90turbo]

Ambient Temp Sensor on the passenger's side may be messed up causing it to think it's a different temperature inside the car than it already is, because IIRC when you put it on 85* it will go full heat regardless of temperature inside the car.

 

[RazoE]

good call, I didn't even think about that..

do you know how to check it?

 

[giterboosted]

Bump for this, I wana know too

 

[Poodles]

Ambient air sensor, light sensor on dash (especially if it's missing it's cover)...

 

[kotu100]

this happened to me, my ambient air temp sensor was just unplugged. just pull off the dash trim on the pass side and check it thru there.