92 300CE rough running - intermittently
 

My 92 300CE is a great car, high compression straight six engine and very good highway performance. However, it has developed a "gremlin" which appears now and then and I am baffled by it. Sometimes the car starts and runs perfectly. Other times, it will suddenly start to "stumble" and run rough -- without power, stalling if you try to give it the gas?! The next time I start it , it may run perfectly again???

It seems to be fuel flooding the engine or injector problems, but occurs only intermittently.

Do you have any idea what could cause this situation? I have considered the fuel pump, but it runs with full power most of the time and starts perfectly.

Thanks for any ideas, Ben Carter