I have a 1990 190E 2.6 Auto which was overfueling .Replacing the metering head which had a seized needle has brought Co mixture down to 1.25 and runs well. The cold start injector keeps pulsing while engine is running and brings mixture up again. Engine runs 1.25 with injector removed but will not cold start.The temp switch has also been replaced.
Anybody know what could make the cold start injector keep pulsing. Any help would be much appreciated . Thanks, Mark..

 

depending on the system on your engine.

thermo time or fuel pump relay.

you got 103.983 or 103.984?

the newer one is actuated by engine control unit.