air condition

Hi everyone,I have a 1998 Lumina car with a 3.1 engine.I have a problem with my air condition.It gets cold but when i accelerate it stops blowing air out the vents,when i slow down and get off the gas pedal out comes the air.Can someone please help me with this problem.Thanks in advance

Richard

It still blows air out the vents, but it doesn't blow out the vents that are aimed towards your face/upper body.

Ever GM vehicle I've been in does this... when going up a hill or accelerating the air stops coming out of the front vents and comes out the vents towards your feet and windshield

It must have somethign to do with a vacuum but it happens in our lumina as well.

it does? My ac blows out of of all the vents no matter if I'm accellerating, decellerating, or going up a hill.

Sounds like some kind of vacum problem im sure. So when you accelerate couldnt the engine require more vacum to some parts of the car causing it to take from the a/c or if there is a slight leak in the hose that comes to the vacum container that pulls the vents to the defrost? I would think that the vacum hose that makes it switch from vent or a/c to defrost could have a hole or something along those lines.

the main feed vacuum line to the control unit in the dash has a one way valve in it to hold vacuum in the lines to door accuators. If this valve sticks open the engine will draw all of the vacuum from the heat/ac and the vents direction will change. :biggrin:

hey, question for all of you guys.... Whats the difference between "AC" and "MAX AC" in my lumina? I tried them both, and both seem to give me the same thing. Just wondering?????

Max A.C. puts your blower motor at its highest speed and also doesnt allow your compressor to cycle at all ,,normal A.C puts the blower at a slightly lower speed and allows your comressor to cycle when the inside of the car reaches a certain tempature as per your setting on your temp slider or dial

ok, thank you. On more quick question by cycle you mean what? I'm sorry, I'm stupid when it comes to AC. Thank you.

Cycle means the compressor clutch engages the compressor and disengages it (so turns it on and off)

When you have your A/C on regular, it cycles on and off because it can keep your car cool without having to be on all the time. Max A/C should keep the compressor kicked in all the time, for those days when it's really hot.

During Max A/C the fan motor also should kick into a higher speed as well...

yes what he said lol!

max ac will also recirculate the cabin air rather than draw in air from outside, allowing for a cooler temperature inside. It's easier to cool the air inside because it's already somewhat cool to begin with as opposed to the outside air.

I thought turning the temp knob into the detent locked the compressor on. I can't remember because it's been so long since I've driven it.