Water puddle = dead 300e
 

My car died after going thru a puddle the other day. Called AAA - felt stupid for not driving the 240D - and just sat waiting. The car tried to fire once when I tried it and so I just sat for about 45min, and it started normally. Surged a bit in fourth around 2500rpm but that went away after a few miles and all seems well. My question is what's the likely suspect to seal. No fuses or OVP out - the car just died.

crash9, is the lower engine encapsulation panel still on your 300E? If not, that would help avoid a similar problem in the future. Of course, even with the lower encapsulation panel installed if you drive through a 2 foot deep puddle you're apt to have problems.

Hard to diagnose without knowing how wet the engine got and where it got wet.

Usual suspect would be the distributor cap. If you have the M103 motor, that forward mounted distributor that lies on it's side might have gotten wet or the ignition control unti mounted on the fender well.

No - it's long gone and the reason I got the car as a parts car for 700$. After checking it out I gambled on replacing the oil pump, chain and sprocket that along with the pan was taken out when the PO hit a step ladder in the road:D
It's got great pressure and seems perfect, so I sold the other one:)
Coil conector?

As an update and a ? The car seemed fine and started right up the next day, but during the Monsoon here I've been driving the 240. So yesterday after sitting for a couple weeks I went to drive the 300e and it would not start. Seemed to try to fire just as I turned the ignition switch off. Haven't checked it completely yet but what dies from just sitting two weeks after a little wetting? This is the second one of these that I've had and dispite everything they seem to start very easily.

Maybe just a coincidence the problem started after you going trough the puddle.
Maybe the fuel pump is going bad.

Had similar problems on my 190e 2.6 that went on for a couple of years...kept replacing dist. caps and rotors before I noticed some serious anomolies in the replacement parts.

"O" ring seal on dist cap....often does not come with replacement caps, so get's overlooked when changing...they get hard with time and do not seal well. Your dist. likely got wet and then dried out from engine heat..why car started after waiting a bit...cars with this problem will be hard starting in damp weather too. Note: to change the "O" ring the backing plate for the rotor/dist. assembly must also be removed (3 machine screws).

I have seen multiple replacement Bosch dist. caps from aftermarket sources which cannot seal due to differences in the moldings (there are air gaps above where the "O" ring is supposed to seal) or will actually not fit correctly at all, or will interfere with the rotor....get a genuine MB oem Bosch cap, rotor and "O" ring seal..and replace. You cannot trust all aftermarket parts due to the widespread variations in sources...Bosch has licenced manufacturers all over the world, so not all "Bosch" labelled parts are equal.

I have had at least 3 wrong caps which were ordered as "Bosch" oem replacement parts through various aftermarket sources..some of the rotors did not even fit..In my case this was for a 2.6 motor, which has basically has the same arrangement as your 1989 300e. The worst part is that some of them fit, but I could not tell right away they did not seal...so my problems continued, and I kept looking elsewhere for the source of my grief. Why would I assume my distributor was getting wet, when I had just changed it?.....drove me bonkers.

Thanks for the replies. The pump is running and I've got good spark. I'm afraid the timing just jumped on starting.:(

Just a thought - coil pack? On my car, it was a pain in the butt to get it started when it was wet out and it started running horrendously after driving in the rain. Turns out the coil pack was the problem and wasn't working properly when it was wet out/when the car got wet.

Might be worth replacing if you've never done it anyways (my local mechanic said its always good to replace even if its not the apparent problem)