Intermittent mis-fire on 230E

[googolplex]

Wondering if anyone has had similar problems with their W124.  My 1989 230E starts fine and idles OK but occasionally (every few weeks or so) it will mis-fire quite severely when accelerating. (cruising at constant speed is usually OK)  Other times it runs just fine.

Turning the ignition off and re-starting immediately (two or three times if necessary) occasionally solves the problem.  I've replaced the distributor cap, rotor arm and HT leads but the problem still crops up now and then.  Any ideas out there before I take it to a dealer?  I thought perhaps it might be the fuel pump(s) or a dodgy relay?

Cheers,
Sam

 

[Andy]

Hi

Sounds like damp getting in. If you fitted dodgy leads and caps that won't cure it.

Only the proper stuff. Try a bosch distributor cap, and try it again. If you fitted one of these rubbish from ECP then they never seal properly and cause other problems later.

Regards

Andy @ www.mercedesservicing.com

 

[Russel Weston]

Hi there Sam. I have had similar problems and although your car is much later than mine I believe there are not to many engine differences. My probelms have definitly been related to the Fuel Relay. I took a 12V feed from the coil and used it as a shunt to by-pass the relay only. What it means is that as soon as the key is in the "run" position then the Fuel Pump is always on. I have replaced the regulator twice, but this definitly works.
Good luck

 

[googolplex]

Thanks for the advice.  (The cap and rotor arm were genuine parts and the new leads are Bosch).
I guess I'll try replacing the relay and hope that cures it.