1991 190e intermitent starting problem

If I could page the font of all knowledge!
I have a 190e 1.8 fuel injection with an odd problem.
It starts mostly first time, every now and then it refuses to start - when
it goes into this mode I can't hear the fuel pump spinning up, although it will do this on the first attempt. If I leave it for a couple of hours it usually starts which would indicate possibly the engine is flooding.
I've checked the usual electrical bits and pieces and can't see anything obvious that may be causing this - anyone got any bright ideas??
TIA
Buzby
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What makes you think the engine is "flooded"? Is it because the car will start if you "floor" the accelerator and hold it there until it starts?
My E320 had one leaking fuel injector that "flooded" the engine only when it was hot, but it always started with (a delay and) a stink of unburned fuel in its exhaust. Cold starting was fine.
Rather, I believe your engine lacks fuel. There's a fuel pump relay (like a switch) for the electric fuel pump. These relays become intermitant and poor starting is often the result as well as otherwise inexplicable stalling while driving.
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Fuel Pump Relay is my first suspect. Crank sensor is second suspect.
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This was my thought as well - I don't appear to have a relay - any ideas as to location. It's not in the fuse box and I can't find any mention of it in the Haynes manual - and there's nothing obvious that I can find anywhere! Cheers
Buzby
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Fuel pump relay is behind the plastic shield behind the battery.
It runs one second just af turning on ignition. It will run again, when cranking the engine or when reaching normal RPM.
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Thanks Jens - I'd have never found it otherwise! Hopefully German & Swedish will have one in stock - otherwise double the price for a 'Merc' one
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