New fuel filter now makes the car run rough (!!!)
 

Hi everyone
this is driving me insane. I just changed the fuel filter on my 300E after my hunch that it was the original one (1987) and full of sediment was bang on. But no sooner can i congratulate myself, i have discovered that now the car drives rough, like it's missing on one pot. I have noticed it starts better though.

can anyone advise? Is this normal? By the way, it does not have an o2 sensor fitted as the previous owner changed the exhaust at some point and opted for one which didn't have the plug (i guess a cheaper system)

Any advice would be greatly appreciated

martin in beirut

I wonder if someone in the past has adjusted the fuel mixture there at the fuel distributor? Possibly a vacuum leak?

My 190E 2.3 runs like a dream most of the time, but now and then, will sit there and randomly mis-fire at idle at a traffic light, and then other times, run like a song again. I replaced the fuel pump, filter, and the accumulator, as mine was dripping fuel.

Do you know the history of your car, or are you in the dark like I am?

Good luck!

some fuel filters filter in one direction