Hi sorry If I may have overlooked the answer to this issue but I'v read a lot and nothing seems to be working....

I bought a 300E 3.0 L6 this summer and it was running super smooth until it got cold.

The engine cranks but won't fire. Had the starter replaced (killed it after trying too much). Fuel filter replaced, From chassis and to chassis pumps working good-pumping at 80 pounds. Relays checked.

Last night got it to idle, but rpm would drop when i touched the throttle.

After letting it idle for couple minutes it ran and stalled for about a mile then ran excellent. Help !!

I have the exact same car with the exact same problem!
I would like to add that the car cranks fine... and when you stop cranking, a puff of blue-grey vapor comes out of air filter housing.
I'm thinking of replacing the coil because it seems that even though there is plenty of juice to crank the negine, there seems to be little spark. ALSO, the problem is more pronounced when I'm starting off from a stop light while running the heater/ac.

If my car (300SE, m103) starts to behave like this, it is usually time to replace the distributor cap and rotor.

Rob

vsjabbal, recommend inspecting the condition of the distributor cap, distributor rotor, ignition wires and air filter. Replace as required. A weak coil would cause the engine to run poorly. Also, the oxygen sensor should be replaced every 60,000 miles.

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Fred Hoelzle

Most likely culprit is one of the temp sensors for the CIS system, or the idle air control valve/solenoid. Could also be a non-firing cold start injector.

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