Atrus

iTrader: (1)

Hey guys, I am having a problem with my car's hvac controls. For reference, this is a 2000 3.8 Firebird M5, with about 130k miles.

So I had my car painted the other day, and when I got it back it felt like the heater was on, pumping heath through the defrost vent and under the dash as well, but the temperature control was set to cool air. I had a problem with the controls before in my LS1 bird, so I tried following the vacuum lines to see if there was a leak somewhere, but I have not found any thus far. If I turn the A/C on, or any other setting, only really hot air comes out. Also I noticed that when travelling on the freeway at high speeds, it seems like the heater is pumping out more heat than normal. All the settings on the controls work as far as front vents/defrost vents (it pumps air from the right places, just always hot regardless of what the temperature **** is set to).

On a side note, don't know if this is related, but I noticed a few months ago that when I run my A/C for long periods of time, water builds up underneath the rug in the passenger's side feet area (it is not coolant, it is water).

Any help in this matter is much appreciated. Happy new year everyone!

Chawlz

As far as the water in floorboard, a/c system will build condensation and drip water. I'm not sure about f-bodys, but some cars have a little drain tube leading to outside under the car. If the drain gets clogged, it can leak into the floorboard.
Longshot, but the water probably could have damaged the mechanical flapper that switches ac / heat

Atrus

iTrader: (1)

Alright awesome, I'll look at the drain tomorrow morning and hopefully it is just clogged, but as far as the "flapper" that switches the temperature...where is that located?

GodSmackit

The door that opens to direct airflow may be stuck in heater mode. You should find a valve to operate this. May be a vacuum leak there or faulty valve. As far as water on floor, I have experienced this. It was the condensation drain tube outside the fire wall that was stopped up.

bayer-z28

iTrader: (14)

^ If you pull the HVAC control panel off there's a wire/cable deal that hooks to the Blend-door. That's under the pass side somewhere. If you take the glove box out, you may be able to see it, or take the pass kick panel off yo may be able to see it.

And the position selector (Vent, defrost) is Vacuum controlled. There's a small vacuum line in the back of the intake for this. Should have a small check valve on it.

wssix99

iTrader: (5)

The flapper is under the passenger side dash and inside the ductwork that lives there. If you take the lower panel off, there is a cover that you can unscrew, which will expose the flapper and pivot. There is a cable that runs from the temp control to that point, which actuates the flapper.