I know that there are a lot of threads out there addressing this problem and I have read as many as I have found in the last few days.

Here's my problem:

My 91 300e 4matic was having some problems starting, I would have to keep the starter engaged an extra second or so. The other morning my car would not start (it turns over fine) when it was 30* F, I tried it again when I got home from work (40* F) and it still did not start.

My Questions:

Could this be the water temp sensor? Would this prevent the car from not starting at all? Would an adjustment to the EHA be helpful?

Answers to these questions and any hints on diagnosing the problem will be much appreciated.

Brian

try searching the list again. There was a recent thread that started last december and went around for a couple months. Turned out to be the fuel pump. But I can't recommend throwing parts at it. The thread would be useful because there's lots of good advice for diagnosing the problem. Literally could be dozens and dozens of things.

I don't the think the EHA or the water sensor is where I'd start. You could attach a timing light to the plug wires to ensure you have spark. Then I'd shoot some ether into the throttle body while trying to start it up (depress the gas pedal a little too). If it sounds like there's combustion then you know you've got a fuel system problem. Next steps would be to verify the operation of the fuel pump, cold start valve, and the idle control valve. fuel pump is pretty easy - try to start the engine and return the key to the "on" position - if you hear a humming from the back of the car that continues for a second or two then you know the main pump is functional.

Good luck

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89 300te 222,222
92 300e 190,000

fuel pump relay was the problem.
check this post http://www.peachparts.com/shopforum/showthread.php?t=118676

I'll check out the pump and relay today, that is if it stops snowing. We received about 6 inches last night.

Waiting for spring to arrive.

I checked for the pump relay, but this being a 91, the relay is part of the MAS. So I disconnected the battery, removed the MAS and checked out the condition of the metal connectors/pins. They all looked clean, so I replaced the MAS and reconnected the battery and attempted to start the car to listen for the fuel pump. The car started right up, no problem. I have started the car up a half dozen times in the last day and taken it for a test run. Still no problems.

However, I am hesitant to drive it any real distance, afraid that I will have the same problem again. Does anyone have any insight on what the problem may have been? And if so, what I can do about it.

Thanks,
Brian

my fule pumo relay looked like new but when I opened it inside one of the contacts was cracked. Some soldering did the job.
ACM