Devius

Does the compressor only come on when the climate control is set at or below a certain temperature? Or is it on all the time unless you push the ECON button?

Andy Hedin

It is potentially "on" all the time, unless you push the ECON button.

ToastR

the compressor is off and on as it thinks it needs to be unless ECON is pushed or it disengages based on the throttle position to free up more power for passing, etc.
Sound right Woofpup?

Ming02

I've noticed that when I turn the car off I could hear a whirring sound. (a sound that could be compared to what the Millenium Falcon would sound like powering down) When I have econ on, that wrirring sound was not present. So, since the colder weather has hit I've kept econ on and I'm watching my gas milage to see if it makes a difference.

jquattro

That is what I have found as well. I use the econ button like I would an A/C button.

Devius

I'll listen for that today.

Bob Petruska

A/C cooling fan noise.

jquattro

You usually hear it right after you turn the engine off.

Devius

not.

woofpup

time unless Econ is enabled. While driving in cold rain last week, I was turning off Econ to kick the AC compressor on to defog the windows. Even though the outside temp was lower than the set temp and even though I had NOT pressed the defrost button, the compressor stayed on the whole time.

It may kick off for heavy throttle use, but I'm not sure - I didn't notice any surges of power though as if the compressor was suddenly disengaged (I have a 3.0, and it could always be different for the 1.8T anyway).

Anyway, the service manual says that it is a clutchless AC compressor (which would make sense if it's staying on the whole time when not in Econ), but I'm still trying to figure out what happens in Econ mode when the compressor is disengaged...