Did not drive the 91 300E w124 for the past 10 days or so... very wet weather, lots of rain.
Disconnected the battery, because I suspect a phantom battery drain.
(Ongoing saga with the electrical in the vehicle:

http://www.peachparts.com/shopforum/tech-help/371580-electrical-issue-close-getting-solved.html

http://www.peachparts.com/shopforum/tech-help/366497-check-engine-light-after-key-out.html)

Thought I was getting close to solving with the #9 fuse clue - today being a nice sunny day, I decided to drive it - it stumbled a bit at first, but after warming up, seemed fine.

After a short ride to the dental office, it would not start when I tried to go home.

So it is stuck in the parking lot.

It cranks, but will not turn over. Not a normal sounding crank, like stumbling.
(Reminded me of the sound when the OVP needed to be replaced).

I checked the fuses in the OVP, both were ok.
Checked the pressure in the gas tank, not much there when gas cap was removed.

A nice lady who was driving a MBZ, stopped to give me a ride. She mentioned that it sounded like a fuel relay failure that happened to her once.
She said to tap on it, and it may fix it to at least get home.

Could it be the fuel relay? Sounds like fuel is not making it to the engine?
Don't know, suggestions please!

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1991 300E 124.030 103.983KE 722358 03 412178
207K

1979 240D 123.123 250K (Project car)

2000 Ford Ranger, 187K

2015 Dodge Ram 1500 EcoDiesel 37K

Found this clue:

http://www.peachparts.com/shopforum/tech-help/273629-300e-will-not-start-rainy-days.html

So I tried the starter fluid trick: disconnected the air filter cover, sprayed the intake manifold (I think that is what it is called) for 3 seconds.

Started right up, took her home - she sounded fine.

Course this is after it was sitting in the hot sun for a few hours.

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1991 300E 124.030 103.983KE 722358 03 412178
207K

1979 240D 123.123 250K (Project car)

2000 Ford Ranger, 187K

2015 Dodge Ram 1500 EcoDiesel 37K

What are the Diagnostic Trouble Codes (DTC) telling you?
You haven't mentioned what they are telling you.
I'm assuming that you know how to get them.
There's lots of info on this site by doing a search on DTC or Code Reader.

Without this info, you are just shooting blind.

The rough and stumble start remind me of when my Crank Position Sensor was failing. Also trouble that starts with rain (moisture) is typically a problem with a loose ground wire somewhere.

Let us know what your DTC's are.

__________________
03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio

And it would help if you fill out your profile and tell us where you reside.
Anziani
'97 CL 600 51K

No fault codes are coming up.

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1991 300E 124.030 103.983KE 722358 03 412178
207K

1979 240D 123.123 250K (Project car)

2000 Ford Ranger, 187K

2015 Dodge Ram 1500 EcoDiesel 37K

test fuel pump volume 1 litre in 20 seconds, one of you 2 fuel pumps may have quit, or put in the air and measure amp draw both should be close, when 1 pump goes out stumbleing happens and hard start

And I would try another coil especially if your mileage is 201K and you have never changed it. But you say there are NO codes?
Anziani