More grunt for no money
 

The owners manual for my '99 boxster says that the compressor for the a/c is driven all the time no matter if you are heating or cooling. The only way to disengage it is by turning the fan off. Is this true on later years also? When I do this there is a noticable increase.

I am not quite understand what the manual means. It does not make sense to have the compressor to run all the time without a compressor clutch. I am not sure, may be that is how the auto climate control works.

It should be easy to check, jack up the car and look at the compressor to see if there a clutch. Or call up the Porsche Parts and ask for a compressor clutch for 2005. HTH.

Later

The manual probably means the compressor runs all the time in "auto" mode.

I would agree. I can hear the A/c compressor go off when I move it to manual and turn off A/C button.