Am I missing something? Isn't your car equipped with the Bosch 6 plunger mechanical injection system? This is not D or K jet. You would probably get better info if this post were moved to the Vintage section. Anyway, these engines tended to run rich when properly adjusted and do not like stop and go, short trip drives. Do a proper tune up including air and fuel filters but also check the coordination of the throttle linkages---these frequently get misadjusted/bent causing a rich fuel mixture (the injection pump lever is opened too much relative to the air venturi lever). Do not adjust the idle mixture on the injection pump until you know what you are doing. $$$ or personal injury. You definitely need to read up on this before proceeding. Mark