View Full Version : Lose vacuum when AC engaged

Avant Nate
08-30-2010, 06:37 PM
Boost gauge drops about 6psi when climate control is activated. Haven't had time to experiment with what modes affect what, but at idle, when Auto on Climate control is turned, on the vacuum dips hard as compressor is engaged and remains low. Does anyone know what parts of the climate control are vacuum actuated? Most of my vacuum lines were replaced with silicone a little whiles back.

08-30-2010, 07:00 PM
mine does to

08-30-2010, 07:25 PM
Im pretty sure thats normal. It takes more power to run the A/C hence why you have less vac, the car is giving it more gas because of the increase in engine load, same diff as holding your throttle a little bit at idle.

08-30-2010, 07:51 PM
Yep, it's called "A/C idle-up". Completely normal. You're not "losing" any vacuum. You just aren't making as much.