Rich_e14

I just bought a w201 1990 190e 2.6 , and its running real bad. It would die after a while, so I thought a voltage regulator would fix it. I've already replaced the voltage regulator, spark plugs, fuel filter and air filter and it doesn't die now, but still runs rough.. It hesitates real bad when accelerating from a dead stop and has no power at all, sometime it will stall out. It blows out black smoke when I'm driving it, but runs great on the highway. From information I've gathered from the forums my next guess would be the fuel distributor is leaking inside or my air fuel mixture is off. But from everywhere I looked its telling me the A/F adjustment is a allen between the fuel distributor and throttle opening. Most forums also just talk about the 2.3. I see where it's supposed to be but there's no adjustment.. How do you adjust it on the 2.6?? Can somebody please help me.. This is my first Benz. I've worked on plenty of cars for years, but just learning how to work on mechanical fuel injection. Any information is greatly appreciated!! Thanks

Motorhead Mike

turn off car,turn mixture screw in 1/4 turn,restart car do this until car runs rough. when running roughly turn off car turn screw back out 1/4 turn,and should idle smoothly. you can be more precise if you have a way to read exhaust. i just went through this and my problem now after replacing one of the two fuel pumps is my car won't start. i gone in and out with the screw so what i need to know is what is the starting point. do i take it all the way in and back it out so many turns or what??? any help is greatly appreciated or sympathy or empathy will work just as well