My 88 260e was left unstarted for a month and now when I get it started, it dies in 15 min when left in idle. Then when I try to restart ...Nothing until I let it sit for a few hours. Midas says there is oil in spark plugs so I replaced them. Any sugestions

This a text book symptom of a bad ignition coil. The are fine when cool but fail when hot. Can drive a person nuts.The only oil that you should be concerned about on the plugs would be heavy caked on flake like deposits on the spark plug electrode. If this is the case then it is on one or two cylinders with bad valves guides or worse. But if the car runs OK after you replaced plugs then I suspect the coil. You can go to wrecking yard and buy one, as I am not sure who can test a coil. If it is a older round cylindrical shaped style coil there are not expensive to buy new. I never give advice but may make this suggestions. Stay away from Midas for anything except may a muffler. They are not historically the right place to go for MB advice or repair. Good Luck, Paul

Kevin, take your car to a reputable independent MB-trained tech for a diagnostic check rather than throwing unnecessary parts at the problem.

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Fred Hoelzle