ac blows on the floor when i step on the gass

[tatman762000]

i dont know why the ac blow on the flor when i step on the gass ...when i reach my speed it goes back to the vents what is the cause of this please help

[tatman762000]

i need to know how to fix this

[Corndog Man]

Originally Posted by tatman762000

i dont know why the ac blow on the flor when i step on the gass ...when i reach my speed it goes back to the vents what is the cause of this please help

On my 1999 I had the same problem. The hose came off after having a front bumper cover replaced. I removed the cover under the left front fender with just a few screwes. Checked the hose and it was good except it had come off. I would say you may not get as lucky as me but you do have a vacuum leak.

Corndog...

[C man]

The check valve for the HVAC system could also be bad.Defrost mode is the limp mode for the HVAC sytem. Doesn't seem like your vaccum leak is to bad since it only happens on acceleration.

[tatman762000]

i'm a dummy were is the HVAC at in the car?

[Corndog Man]

Originally Posted by tatman762000

i'm a dummy were is the HVAC at in the car?

Check the easy first with the vacuum. You can do it yourself. My '99 did just as yours until I found and repaired the leak. If you start messing with HVAC and don't know what you are doing..... Well you understand. Go pay the man.

Corndog...

[brcidd]

Look for the black plastic vacuum line to be brittle/cracked/broken near the battery where it goes down to the vacuum reservoir in front of driver's front wheel- the battery outgassing causes this line to break-- you repair it by cutting it and inserting the right sized rubber hose over it- no clamps needed since it is a vacuum line-- I have actually seen replacement batteries sitting on top of the vacuum line from an ACE mechanic's battery install....if the leak is not there then trace all vacuum lines back to engine intake and chaeck for holes-- also be sure the line is attached to the vacuum reservoir under front fender......

[C man]

The HVAC is your whole heating and a/c system inside the car. It includes your vents, blower fan, evaporator, heater core, etc... But like corndogg man said, its probably a vacuum leak. The check valve that I mentioned is actually apart of the vacuum hoses. I don't know the exact location on a lumina . the re should be a three way fitting. Thats your check valve for the hvac system. It basically holds a vacuum for the system under high loads (full throttle means more air less vacuum). Start there and trace the hoses back and check them for cracks and tears or were brcidd said (didn't see that post at first) Yours is probably a small tear or crack since it only happens under acceleration. If it was real bad it would just stay in defrost mode.