Stalling in 300sl

My 1992 300SL MB with 140,000 kms starts up fine first time in the morning but stalls at the first or second stop. It usually runs fine after that. I have replaced the engine wire, the distributor cap, the fuel injectors, the spark plugs and the throttle body has been cleaned. The car performs better but still stalls when the car is first taken out. This has been frustrating for me and my mechanic who is still trying to locate the problem. Any suggestions?

Reply to
silverfox
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Gas engines heat the engine's intake air during the warm-up period - a small duct routes the intake air to a heat source like the cylinder head or exhaust etc. I have the suspicion that this "system" isn't working correctly on your motor.

As the motor warms up this device normally scales back and the computer, anticipating warm air to be available leans the air / fuel ratio. So when the warm air is missing the mixture gets too lean and the motor stalls.

If I'm correct, this should be a simple fix.

Reply to
Take A Guess

If your mechanic have proper tool to electronically view all components, then he would have figured it out. But I would suspect the OVP relay first... Overload Protection Relay.

Reply to
Tiger

As Tiger says, it could be OVP relay.

But it could also be oxygen sensor functioning improperly during its warm up.

Reply to
Jens

Thanks for all your kind suggestions. My mechanic also replaced the overload protection relay, all 6 fuel injectors and seals. The car now runs like new but every other time it stalls at the first stop sign. When I start it up again, heat blasts out of the heating vents, which it did not do before it stalled. Do you think the problem is the O2 sensor

"silverfox" wrote

Reply to
silverfox

At this point, I would say it probably is the fuel pump relay.

Reply to
Tiger

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