rcrone928

I was wondering what the relationship is between the kickdown switch and the bowden cable. I've adjusted the bowden cable tension per other suggestions on this site and that seems ok. Why i'm asking is I can't hold 1st gear past 4500 rpms no matter how hard i hold the pedal down even by starting out with selector in second. Car is 83 us auto. I'm not so sure the kickdown switch is even working. I tried the click test with engine off and ignition on and didn't hear any clicking. I'll do electrical tests when i can get to them. Which system does the down shifting? The kickdown switch or, the bowden cable or both. Thanks. Rob

Barry Chan

mine is like that too, it will go to red line on second, not yet on third, didn't want to risk getting a ticket

yardpro

redline in third is about 140mph......been there...lol

i have been playing around with mine as i have the same issue.... 1st will frequently not redline, but second always will....

Barry Chan

i think i read somewhere long time ago that this is normal?

rcrone928

I guess what I'm really asking is why do i need the bowden cable hooked up if the kickdown switch supposedly causes a down shift or conversly, why do I need the kickdown switch if the bowden cable operates the downshift? Do the both of them have to work together some how? Thanks.

Rob M Budd

You control when it shifts by adjusting the vacuum modulator.
The kick down switch tells the trans to downshift.
The bowden cable tells the transmission where the throttle is. Adjusting it doesn't do much except causes hard shifting when its out of adjustment.

I think these are the basic functions if memory serves me right.

All three work together. And must be adjusted/working properly to produce the desired result.
Adjusting the vacuum modulator can be done to shift at low RPM (low vacuum) or high RPM (more vacuum).
The workshop manual has a section that covers it.

WallyP

Porsche appears to have set up the upshift speeds on the earlier cars so that the transmission shifts out of first gear well before redline. I suspect that is because redline comes up very quickly at full throttle in first gear.
The Bowden cable is the primary adjustment affecting shift speed when the kickdown solenoid is not energized. It is important that the cable be properly adjusted.
The kickdown solenoid, when energized, makes the transmission more reluctant to upshift and more eager to downshift.
The vacuum modulator has little effect on shift speed. Its primary function is to adjust the firmness of the shifts.

rcrone928

Thanks Wally & Rob. Again you guys have answered my questions and really cleared up of how things work.

rcrone928

Well I found the kickdown does'nt work because THERE IS NO RELAY IN THE CE PANEL!!!!! wHY DID i NOT LOOK THERE FIRST.