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1991 Mercedes Benz 300e Repair Question


Topics covered: Spark, Fuel pump, Engine.
Mileage: 164,000 miles.

Asked on October 21, 2011

1991 300e stalls after car runs for 3 to 5 miles and will start back up after 30 minutes. Do you think the crank sensor is defective? I checked and replaced a bad fuse on the overvoltage relay. I dont have spark or coil trigger when problem occurs.

I replaced cap,rotor,spark plugs and wires. Ignition was arcing through cap and wires. Problem was present before I replaced these parts. I used O.E. parts not cheap parts.
Avatar Asked by portillor

Answer

Replied on October 26, 2011

http://www.2carpros.com/articles/car-cranks-but-wont-start

Next time it refuses to start don't wait for it to make up its mind-do below immediately to determine if its fuel or spark problem

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if okay-check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs,coil's resistances,cap and rotor,distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing

Tiny Answered by rasmataz
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