Accelorator Pedal Not Fully Returning

[arbita1]

I think I finally found the cause of my intermittent high idle. And it's not CIS related as suspected.

Today when my idle was hovering at about 1300 RPM I had the idea to reach down and pull the accelerator pedal back. It moved back about 1/8" and the idle went to 950 rpm. As I was driving and stopping. I would use my foot on top of the pedal to pull it back and every time the idle would drop to normal.

I opened up the pedal cluster cover and found a disgusting mouse nest in there around the pedal cluster. (It's been a rough winter with mice this year.) I vacuumed it out. And lubricated all the pedal joints with lithium grease.

I haven't driven again but I can still feel that I can pull the pedal back. I checked the throttle in the engine bay and I can pull that back too.

I am not sure if I may need an adjustment or a new spring. Not sure what brings the linkage back to the idle position. Bentley book has nothing on it. Haven't checked elsewhere yet.


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[KNS]

Check underneath too as it runs past the transmission.

[schoward]

There is a (secondary?) throttle spring that attaches to the #2 intake runner - little hole on the underside if I recall. Make sure it's there if you just put everything back together. I have a spare if needed you could have for free.

A little spray lube on bell crank bushings and the throttle console on the engine may make a difference if things have been sitting.

[arbita1]

Originally Posted by schoward

There is a (secondary?) throttle spring that attaches to the #2 intake runner - little hole on the underside if I recall. Make sure it's there if you just put everything back together. I have a spare if needed you could have for free.



A little spray lube on bell crank bushings and the throttle console on the engine may make a difference if things have been sitting.

Thanks. The spring is on. I went out today and it seemed to be ok. So maybe lubricating the pedal cluster worked. We'll see if it happens again then I may have to adjust the linkage.


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[steely]

I know I am late to this thread, but as others have alluded to, there are 2 bell-cranks in the path of the linkage. One is on the side of the transmission, and the larger is on top of the engine.
Both of these cranks have plastic bushings that break over time, introducing some slop. Instead of pivoting nicely on the bushings, the cranks can wobble if the bushing isn't there.

The one on the transmission is easier to see, so try to inspect it. I am talking about items 12 and 13(2x) in the 83 PET page/figure 702-10.

[Dmitry at Pelican Parts]

Check out the link below to rebuild your pedal cluster. Please let us know if you have any questions.

Porsche 911 Pedal Cluster Rebuild | 911 (1965-89) - 930 Turbo (1975-89) | Pelican Parts DIY Maintenance Article


-Dmitry