Audi a6.. heat AND airconditioning only work when foot on the gas or moving

#1

I have a 98 audi a6 and my heat nor my air conditioning heat or cool unless the gas is revving and or moving… the blower works…but no heat or cool… help

#2

Some vehicles use vacuum motors to control the various flaps within the HVAC system. If your car has a vacuum leak the flaps won’t move correctly or stay in position. When you accelerate there is less vacuum, when you cost or idle at a light there is more, and the symptoms you describe could be caused by a vacuum leak.

If your Audi uses electric motors to move the flaps, then it’s not a vacuum leak.