Last night AC worked fine on the way to my destination but when I came out the front would not work. The rear AC still blows cold as ever. I can feel a very small amount of cold air coming through the front vents but way less than even when on low. Check fuses and relays under hood and all are fine. Any advice?

 

H-valve sticking or a leak and the system is low.

 

What is the H-valve? Noticed today that cold air seems to come out a little bit when pushing the gas pedal and completely stops when idle.

 

The h-valve is what meters the freon into the evaperator. If you follow the a/c lines under the hood until they get to the fire wall, the h-valve is what they connect to. A large alluminum block.

 

Can you tell by looking at it if it is stuck? Can it be cleaned or does it need to be replaced?

 

If the H-valve is stuck, then you replace it with a new one.