Hello,
I purchased a 1991 300e 3.0. I helped install a rebuilt trans and new suspension and exhaust. The car runs great for days. BUT every so often I say the car goes into stupid mode. The car starts to run rough and is down on power. The car will not take fuel very well and when you stop and then pull out the car shifts very hard. It may take 3 to 10 miles and then all of a sudden the car is back to normal runs great shifts very smooth. There is no check engine light at all. The car will run fine for days or maybe an hour and will do this again. The car has new plugs, wires, cap. I have checked the plug wires for continuity and they turned out fine. I have looked for lose connections but all looks good. I hope someone out there has seen this problem and can tell me what to look for???? Thanks