Sticking Throttle or Something Else?
 

So, I've been reading about everything I can on this subject, but I don't think anything quite describes my issue accurately. If you don't read my signature, it's an '88 Carrera cab. Here are the facts.

1. When the car is cold, everything seems to work as it should.
2. When the car is warm, the idle will hang up around 1,800 rpm.
3. Blipping the throttle DOES NOT help.
4. If I let off the clutch pedal just enough to catch the engine, the idle will drop down to normal.
5. If I keep the car under 1,800 rpm when warm, the idle will remain where it should.
6. As soon as I drive normally, it will return to the 1,800 rpm idle.
7. I have already replaced the accelerator linkage bushings at the bellcrank housing, to no avail.

Any thoughts on what may be causing the problem? Thanks in advance!

there is a bellcrank housing on the motor, drivers side behind and below the intake.
Have you removed that and taken a look at the bushings and ball cups?

Rich

I saw somebody's fix on that on one thread. It's definitely a possibility, but I'm trying to figure out if that is truly the issue before I spend hours cursing my fat hands that will inevitably draw blood on that repair! Haha!

I did the thread on "below and behind" intake fix. http://forums.pelicanparts.com/porsche-911-technical-forum/609976-fix-binding-accelerator-not-pedal-bell-housing-bushings-not-even-tunnel.html

Test, get below her and disconnect the ball cup connector at the bell housing then check the travel of the pedal and seperately at the Throttle body. This will tell you where it is binding.

Jim

P.S. just be gentle but firm on the ball cup, it needs to be pullled straight out and not at an angle to release the pressure on the internal circlip.

I worried about the same issue for months--binds when hot, works when cold. There is a pivot lever on the bell housing; get someone to manipulate the accelerator pedal while you're under the car, and you will see it. It's mounted on a short shaft that is attached to the bell housing. Don't worry about finding the location, just watch as the throttle is moved, follow the linkage move back towards the rear, and you will see it.
That shaft is exactly the correct length.....when it's clean and lubricated. Real world throws crud into the equation and it starts binding.
Pull the linkage stuff off the shaft--it's sort of obvious what to do--clean everything back to clean metal, and lube, reassemble. No more sticky, until next time, so file this away for later use.
The local mechanic said it was a throttle body, that he had a used one, and would install it for $500.
This was one of the first repairs I did on the wee beastie--I learned lots about Porsches, (yes they do respond to real world physics just like all other cars) and mechanics on this one. Trust yourself, get under the car, and fix it yourself--you'll be doing it more than once during your ownership of the car.