My 450 SL does not like a hot start. When cold starts every time. When hot engine fires, then dies. Any ideas?
Chris

mine has the same symptom when it's anything over normal operating temperature. MB dealer claims I need a new idle valve ($287) but I'm not sure if that is the actual cause of this problem.

Thanks for your comments. If I get anything definitive, I'll let you know.

Once it does start, is there any black smoke, or rough idling?

Larry, once it starts there is no adverse signs axcept that the engine dies, almost as if it is starved of fuel.

You have fuel pressure drop off and then vapor lock as a result.

The system should maintain about 3 bar residual pressure for long enough for the motor to cool. This isn't a problem cold and fuel pressure often drops to zero over night, but builds almost instantly.

Common problem is pump check valve or pressure accumulator diaphram.

------------------
Steve Brotherton
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician

I should have mentioned that the motor also cuts off sometimes when I come to a stop at a light or stop sign. Would that be a sympton of the two causes you mentioned.