[Boxster] Idle problem

[HolmaN]

The problem is continued in this thread: Idle problem - Part II




Greetings,
I've been browsing some other threads, and seen diffrent solutions (by suggestions), but never any reply with what worked and what not.

I've got a boxster from 1998, and problems with the AC. When I turn it on, the idle starts dropping down to 300-500, and as soon as I turn it off, it oes back to normal (800-900).
I've cleaned the mass flow sensor as well as the throtle body, but with no success. (this was before I notice it only happen with the AC on.)

The question: I've seen replies ragarding the sensor located on the throtle body, have anyone managed to solve the problem by replacing or cleaning it?
The first think that came to my mind was the compressor for the AC, it's not stuck, but it might be slowly dying. Have anyone solved it by replacing it or changing the filter / emty the oil etc?

That's the two things that came to my mind.
I appreciate the help!

With kind regards, Jonathan from Sweden.