I have a 2002 Mercedes Benz C240 and the check engine light keeps coming on. Each time it comes on it shows a different misfire. I have recently replaced the spark plugs and spark plug wires and it ran perfectly for a about a month until I gave it a little gas at a stop light and once again it started misfiring on cylinder #4. My new mechanic thinks I need to replace the injector. I was thinking about replacing all of them. Will this will solve my problem?

Thanks in advance.

 

I just had the same problem with mine, they are replacing all the spark plugs, 4 of the spark plug wires, and 2 ignition coils they say went bad. Hopefully it won't happen again like with you, cost me $1200 for all of that. If anything happens with you, please post so hopefully I'll know what to expect down the road if my car does the same thing.

 

Are you using Premium fuel. I have had similar problems with random misfires and found that changing gas stations and making sure we only used premium fuel was the solution.

 

fuel injector dont go bad to often. most liekly the wires arent correctly seated. def make sure your not using **** gas...the cheapest gas you can find. use 89 or better.
if the misfire is moving around then its not your injectors.

 

I have been using premium gas and about a month ago I put injector cleaner during 2 seperate fill ups and it ran fine until recently when I got on it a little. But I am pretty sure the previous owner was putting regular in it. I was thinking about putting some sea foam thru the fuel system. Any suggestions?

 

How many miles do you have on the car? When was the last time the fuel filter was changed? Random misfires are very hard to track down, but just putting parts in is not a solution.

Stick with a good premium fuel and make sure all of the basics are covered, fuel filter, plug wires are all connected properly.

There are many different fuel additives, I would recommend some basic internet search reading before deciding on whether to use one or not.