Jim bailey - 928 International

Yes Dan the decel valve was to limit pollution it is called a vacuum limiter 930 110 173 00 by Porsche. It was also fitted to the 78-79 USA models.

Chuck Schreiber

Funny,

I feel this on the GTS which is new to me and though something was wrong. If you lug in first gear I can feel this bigtime. NEVER happened in the 79. It seems a lot smoother and easier to opporate at lower rpm at parking lot speeds. BTW, both cars are 5 spd.

6mil928

Chuck the rims on the OB look good.

John Speake

The fuel cutoff of the LH under deceleration can be switched off in the software, without loosing idle speed refulation or auto'box speed drop. This might be worth a try.

If anyone wants to try a test chip, let me know. Or anyone with a SharkTuner can make one for you. Just go into the "Parameters" screen and switch off " Cut off fuel under deceleration".

Chuck Schreiber

Thanks Jason, They'd look good on your identical 81 too!

V2Rocket

i always figured that my car would lurch because it was idling enough to keep the wheels moving and the wheels were moving just fast enough to keep the engine at the right speed...lol

this also sort of happened in my infiniti Q45 automatic, it was the fuel pump tho.