Hard Starting 300E
 

Everytime I go to start my car after the cars been "resting" it always takes forever to start. I turn the key, it cranks and cranks and cranks and when i think i got it started, it stalls. Recently it's been doing it occationally after it's jus been started. So what helps a bit is reving it while im starting, but still occationally stalls. I had some work on it a few weeks ago and my mechanic said it needed some new spark plug wires, now i didn't want to have him do it cause i was gonna have to pay much more to get it done, so i figured i'd just do it once i got around to it, which i havn't yet. Would that effect my starting that much? Also would worn Spark plugs do all this? Im going to replace these things with in the month. Also, would fuel injecters have a part in this? Once our school shop become usable (under construction), im going to be doing all this work then.

Thanks in Advance

Hard Starting
 

Did you ever solve this? I've got a hard starting problem with my 92 300E, too.

If the ignition system is not in top shape, it could be one of the causes of your problem.
Other possible causes: Fuel accumulator, fuel pump, fuel filter, cold start valve (below a certain temperature). Been there, done that.
Good luck
jackD

for Chris17H re your starting and stopping 300E
 

One day I tried to start my 86 300E and it started then died. This happened several times in succession. I called MB and they replaced the Fuel Accumulator. It has been starting fine and running well since. Might be your problem.

Al

Hard Starting
 

It turned out the coil was the culprit. Replaced it and everything's fine!

Thanks for the response.

Todd

How did you know it was the coil?

Haasman

Hard Starting
 

The starting problem existed only in cooler and/or wet weather. My guess was that fuel delivery wasn't the problem, otherwise the problem would probably have been more consistent, despite the weather. I didn't really know it was the coil, as I don't have my own diagnostic equipment, but I took a guess and figured I'd start with the easiest-to-deal-with, most common problems. The car has over 150,000 on it and the coil was the original part. I found a guy who would replace it for $110, parts/labor, so I figured what the heck. The coils tend to go on these cars after a certain time anyway. I did also replace the overvoltage protection relay previous to the coil, but that wasn't the problem. But i've heard that sometimes that can be the culprit, too. At least now I know those two parts are OK for another 100,000K or so.

Todd,

Thanks for the explanation.

Is replacing a coil a DIY type job? Is the coil ever replaced at one of the major services, i.e. 120,000 miles?

Thanks,

glenmore
1991 300CE

Hard Starting
 

Replacing the coil is definitely a DIY job -- should take no more than 20 minutes or so. You can find the part at wholesale pricing of just over $100 or so.

I don't believe the coil is automatically replaced at any servicing. I checked back on that on the description of the 120,000 service, which I took my car in for, and nothing about the coil is mentioned. Remember, I drive a '92 300E: it has one coil. I believe other models may have more, or even no coils?