Hi everyone. I have a 1989 E300. It starts up fine, idles smooth. Rev the engine a bit- still runs smooth. After about 10 minutes when it warms up to about the 80 mark, it begins idling rough. Push the gas pedal down and it is runs rough and stops. Will not restart. I tried to start it again after an hour or so, still will not start. Tried starting it the next day and it starts up fine but goes through the same process of idling rough then stopping. I have changed the spark plugs and spark plug wires. Any ideas?

 

Hello and welcome to the forum! Take a look at the link below; this could be the cause of the rough idle.

Mercedes-Benz W124 Resonance Valve Replacement | 1986-1995 E-Class | Pelican Parts DIY Maintenance Article

 

Hello and thank you Pelican Parts. I'm not sure if that is the same engine I have. Mine has a large air cleaner on the right side where the one shown does not.

 

this is my engine

 

Your 89' E300 is part of the W124 platform - our tech article may have been done on a 220E or 260E, but generally the mechanics are going to be the same.

 

Where would I look for the Resonance valve on my engine?

 

My apologies, it seems that we used an M104 engine and you have the M103 - Nonetheless, I would suggest adding a Comment just below the tech article that I linked you to and one of our MB techs should be able to assist. Sorry about that!

 

Okay, Thank you