1971 Mercedes 250 CE with D Jetronic.

Hi Thanks for all this fabulous info. All rests within spec apart from pins 9 and 20. Only have 9 reactions instead of 10. Removed throttle switch and cleaned it with electrical spray. Still only 9 but engine now running. Will this make much difference,S.

Hi Steve,
the TPS has to send this signals while you are opening the throttle to enrich the mixture in acceleration. 
One will not notice in real operation the signals near the end-position of the throttle are missing.
You will have the first version of the TPS installed in the car.
I think, the signals are missing because you had to adjust the switch in a position outside of the normal range because the contact-feelers for the idle-signals have bent <weakened> during the years.



You can see this switch had been adjusted to the end position... and in this position the last signals are missing.
Re-bend the marked idle-contact to the original position and you will have the 10 contacts re-activated after re-adjusting the position of the switch.

It's always a good idea to clean the TPS - but it's no good idea to grease it inside, even contact-spray can isolate, because there is extremely low electrical current there. Clean it - but don't grease the feelers or the board.

Regards
Norbert



 
 

Thanks again, Steve.