I recently bought an 89 190e2.6 with 105k miles for one of my kids to drive. The car is in mint condition, but salls unpredictably and stumbles at the same time on restart. It will then drive perfectly for a day or so. I have checked all electrical grounds(ok), the fuel pump relay, and have run Injector cleaner thru a tank of gas.
I would appreciate a few hints as to which way to proceed from here.(I am replacing the fuel filter this weekend).