1990 300 e m 103 drivability

[reeltapegone]

The car has 41k miles , new plugs,air fuel filters ,O2 sensor, fuel dist potentiometer ( set correctly) etc..When the car is started and is in closed loop it has no issues and will perform normally. When warmed up the car will accelerate to about 2000 rpm and then it acts like the throttle is disconnected. if you lift your foot momentarily it will resume accelerating.


I'm thinking EHA or a vacuum leak somewhere. My friend is a factory trained MB tech , but we are old and have poor memories ! ideas/

[stardiagnostics]

Lots of things to check. Low mileage is a blessing and a curse as nothing has been done in terms of larger repairs.

I would start by checking CIS pressures with a CIS specific fuel pressure gauge and drive the vehicle at your RPM of concern to see if pressure drops in the lower chamber. This will indicate a fuel pump issue. Or one of your two external Bosch pumps are weak.

Again, lots of things to check but I think I would start there.

[reeltapegone]

New wrinkle in the 300e saga. When the engine is warmed up the ABS lamp comes on and the brakes are lightly applied-wont roll in neutral. (-ABS lamp on) and drivability is very poor. When cooled off, rolls fine and drivability improved. I'm thinking I got a bad OVP relay. Can you test them ?