Hanging Idle fixed
 

Just had my car in for a service to repair the input shaft on my rebuilt 915. apparently the early input shafts have a weak point, and mine sheared. so the shop went back in a dropped the motor and tranny to fix it.

when I got the car back the idle would hang at around 2000 once the engine was warmed up. I could get it back down to about a 1000 by dragging the clutch a little with the car in 1st at a stop. kind of annoying, so I started to look into what was happening.

I had just put in a steve wong chip to match my SSI's and 93 octane available here, so I went to his site and looked at what might be possible. checked out the throttle switch and the idle position switch and both were fine.

so I tested the idle by jumping the connections b and c. idle went up like it was supposed to.

next I looked at the linkage up near the intake. I think we have the root of the problem. it was not smooth. felt like it was hanging up somewhere. so I started checking all the possible adjustments that should be right. I could push the linkage and get the idle right down at 800. so I got under the car and checked the linkage next to the transmission. definitely hanging up somewhere, and now the idle was up around 2400 and I could not get it back down. so I went further to where the cable goes through the rubber boot and into the car on it's way up to the pedal linkage.

after plenty of jiggling and re-starting the idle finally fell back down to 800. steady as a rock. revved it from the linkage near the transmission. worked perfectly, and the same at the linkage by the intake.
thanks to Pelican, Steve Wong and the bentley manual I got it fixed just right. took it out for a spin and scared myself silly... again. love these cars!:cool:

I have the same issue with mine,first it was the linkage on the gearbox that was binding and unless i have to take that apart to clean and lube it again i will go deeper like you did and follow the cable up to the pedal !

It gets annoying because it only seems to happen when i pull into a parking spot or at a traffic light when there are a lot of people around ... lol
Thank you for the info !

Cheers !
Phil

I had problems with my car ths year too. The linkage is a bit more complicated since I am running webers. I couldn't fina anywhere obvious where it could be bingin so I sprayed WURTH HHS2000 in all of the ball sockets. worked the throttle a few times and left it over night. The next day, everything was fine.

That stuff is nothing short of amazing.