air conditioning blowing from the wrong vent

[rktmn]

Well I finally got my A/C working. I though that I had a short circuit, but allit needed was gas.

Anyway, now when I am driving, as I accelerate the air will stop blowing from the pannel vent and start blowing out of the defroster vent. This only lasts a few seconds and as the engine revs come down, the air returns to the panel vents. At first I though that the blower was cutting out, but instead the air is simply being diverted from one vent to another vent.

It only happens when I am driving. If I rev the engine standing still, it does not switch.

I guess that it has to do with the change in engine vacuum actuating the defroster vent at the wrong time.

How would I go about looking for the culprit? Could it be a leaking vacuum tube, damaged vacuum actuator or the climate control panel, EATC.

This is very anoying especially during the hot part of the day?

Jose

 

[Off Road SHO]

Jose,

That is happening because our cars, along with most others, use vacuum to switch the air direction from its' default position, "defrost", to any of the other positions. When you open up the throttle, you have less vacuum to play with so the car makers put in vacuum storage containers to help moderate the ups and downs.

Tom

 

[rktmn]

So how do I fix it to keep it fro going to defrost?

Jose

 

[Rockledge]

A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times (large leak), or only when specific functions are selected (indicating a leak in that portion of the circuit). If it is a vacuum leak you suspect, consider these causes:

- No vacuum to the function selector switch.
- Function selector switch leaks vacuum.
- Damaged/kinked/pinched vacuum hose.
- Leaking/damaged vacuum control motor.
- Leaking/damaged A/C vacuum check valve.
- Leaking/damaged A/C vacuum reservoir tank.
- Vacuum actuator arm not connected to the door crank.

 

[rktmn]

I have noticed that this change in vents only happens when it is on "Max
A/C". It doest happen if I have it on "Panel/ Floor".

So I guess that the small leak is isolated to that vacuum circuit.

I guess that I will start by removing the EATC and check my lines behind the panel.

Thanks Rocklege.

Jose