My 1995 E320 is skipping a beat, has a very slight misfire that does not seem to affect its performance but is really irritating me and making me worry about it worsening. I have already replaced the plugs with the specific Bosch plugs that are required and the coils and plug wires were replaced not very long ago. Maybe 10k miles. It has 214k miles on it. The idle still appears solid but if you put your hand on the top of an open door you will see the misfire in your hand.
I am just wondering what I could look at after the plugs and the coils and wires? Is there a code I might be able to pick up? The check engine light is on already because of an EGR problem that I cannot get right after cleaning out the tiny pipe that goes into the manifold during a head removal job and replacing the egr valve.

Thanks very much,
Jim Lee

Jim, did you remove the EGR pipe and clean it thoroughly? A tech at our local MB dealer told me that the dealer techs remove the pipe and use Berkebile 2+2 Gum Cutter to clean it. It's necessary to remove the fuel injectors and the intake manifold to remove the EGR pipe. I'm preparing to do the job on our 1995 E320 soon.

Apparently using a length of speedometer cable and a variable speed drill to clean the pipe in-place doesn't do an acceptable cleaning job.

When did you replace the fuel filter last?

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Fred Hoelzle

I had it completely off the car when I replaced the head gasket. Ran cleaner through it and blew it out clear with compressed air. New EGR valve also. I have changed the fuel filter but it was a while ago. I have also cleaned the injectors. It is so subtle a miss that I am thinking it has to be an electronic spark issue.

Thanks,
Jim Lee

Jim, recommend using Beru ignition wires. In my opinion they are better quality than Bosch. Did you replace the 3 connectors when you replaced the ignition wires? If not, one of them could be the source of the slight misfire.

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Fred Hoelzle