Hello,
My 1976 914 2.0L just had a new tranny installed and we were taking it home when we realized it was jerking. We had to keep the RPMs higher than the car seemed to have liked, but none the less we made it home.
Now we're wondering how to fix it, can anyone help us?
We've heard take out the Throttle Valve Switch and replace it, or clean it.
How would i go about getting a new one? or fixing the one i have?
HELP PLEASE

TPS, throttle position switch.....I've been told that you can reposition it so that the contact is in another area instead of at idle....but it's a bit of a bandaid. You can try cleaning it.

Pretty sure they are NLA, but you can try the usual suspects like GPR, AA, Parts Heaven, dC Automotive and look for a known good one. Maybe by now they started doing repros....

I have a 2.0 throttle body and switch available if you need one.

to test it unplug it! if the jerking goes away then its out of adjustment or dirty.

Isnt it an essential part to the car?
wouldnt removing it cause something that i really wouldnt want, i.e. sticking, no control of throttle?

The TPS tells the ECU when the engine is at idle and full throttle. If you unplug it to test it the ECU along with the MPS controls the AFR (air fuel ratio) and the car runs fine but acceleration isn't the best.

its just a quick way to determine if the TPS is causing the problem. Wornout traces means you will have to source another. Usually, careful cleaning and adjustment corrects the problem.

Edited.
Posted wrong suggestion of help.

It's like Geoff says, here's a little more info. In the 2.0L 914 D-Jet, the throttle switch serves two major purposes. It tells the ECU when the throttle is closed (idle and overrun condition), and it tells the ECU when the throttle is being opened. There's a set of wipers that are connected to the throttle shaft that contact traces on a fixed board. When you open the throttle, a drag switch in the throttle turns on, and every time a wiper crosses a track (there are 20), a signal is sent to the ECU that causes a short injection pulse to be intermixed with the injection pulses already being sent. These extra injection pulses enrich the mixture and provide better acceleration.

When the switch is dirty and worn, you keep getting these extra injection pulses due to extra contactings while you're holding the throttle steady. By disconnecting the switch, you eliminate those extra pulses and the cause of bucking. You also make the car accelerate more sluggishly - but hey, it's a 914, who can tell?

If your bucking goes away when you disconnect the TPS, I would suggest opening the unit and cleaning the board with contact cleaner, then lubricating the trace areas with a contact lubricant like Stabilant 22.