Drive a 1993 300e with 136 k miles that has a hard time starting intermittently when the car is hot and the environment temperature is above approximately 75 degrees. Will start fine when cold. When the problem is present, the car will crank, however, will not start. The problem only seems to occur when I return to the car within 30 minutes of having turned it off. Errands have become something of a game of chance because of this. Most times I've continued to try to start the car every 5 minutes or so and within about 20 minutes it'll start. When it does eventually start it starts as if nothing is wrong, i.e. no rough idle. Today, however, the car would not start until having it towed to my mechanic. The environmental temperature was 96 degrees. It then started on the mechanic's second try (inside the cool garage) before any testing could be done. Have read numerous posts and want to make sure I understand that this could be a symptom of a myraid of problems including faulty... OVP, fuel pump relay, fuel pressure accumulator, ignition coil, and/or ignition module. Could someone provide some good advice on what the most likely culprit of the problem is and what might be the most reasonable approach to solving it?

Tom, my 86 Euro 500 SE dose same as your car,on page 14
my owners manual says to srart engine at operating temperature turn key in steering lock clockwise.Do not depress the accelerator.If the engine fails to start after approximately 4 seconds, fully depress accelerator and continue to crank until the engine fires regulary.Release the key and ease off the accelerator.At very high collant temperatures the starting time can be reduced if the accelerator is depressed slowly from the very beggining of the starting process.This has always worked for me but sometimes it can be pretty touchy as engine will run rough for a few second and you need to modulate the accelerator and be carefull as it will suddenly clear itself and you have to be carefull not to over rev it if your engine revs as freely as mine.check search for a fix.........
William Rogers......

Thanks for the info. William. Unfortunately, I've read through and executed what is stated in the manual many times with no resolution to my problem. Also have my doubts that the problem is associated with extremely high coolant temperatures because in some instances I just have not driven far enough for that to be the case.

OVP!!!!!

Just change it with the updated version, and your problem will be gone.

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2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

OVP!!! Yah! OVP!!!

Phil in FastLane should just put a direct link on the page just for that part!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car