86 300e stalling

[MEIN GEIL MERC]

I JUST BOUGHT MY FIRST 300E ON EBAY FOR 1000- USD(I KNOW,THE MOST EXSPENSIVE MB IS A CHEAP ONE!) IT STARTS UP AND RUNS WELL INITIALLY,AND THEN THE IDLE WILL START TO BE A LITTLE ROUGH AND THEN IT WILL STALL OUT AND TAKE ABOUT 15 MIN. BEFORE IT STARTS AGAIN. IT IS VERY INCONSISTANT,I HAVE DRIVEN IT 10 MILES OR SO BEFORE IT ACTS UP AND SOMETIMES IT WILL ACT UP IMMEDIATLY ON START UP. I'VE STARTED WITH REPLACING THE OVP RELAY TO NO AVAIL.
THIS WEEK I'M REPLACING THE FUEL PUMP RELAY AND THEN CAP/ROTOR+PLUGS. ANY SUGGESTIONS WOULD BE GREATLY APPRECIATED!

OH YEAH, I'M ALSO GOING TO REPLACE BRAKE PADS AND ROTORS. IS THERE ANY TRICKS OR TIPS?!
THANKS !!!!!

[nglitz]

Don't just throw parts at it, that's what makes a cheap car expensive. I've got an '87 260E, very similar. Just replacing everything you can pull out & find in a catalog typically won't help. Unless you're the lucky type. I'm usually not.

If the ABS light was off while driving, the OVP was probably ok.

Unless sparks are leaking out, the cap & wires are probably ok, certainly not something that would fail after ten minutes of driving and then come back to life after a rest. Look under the hood at night w/o lights. Or, give it the superman test.

If the fuel pump comes on with the key turning on, it's probably ok, too. There are terminals to jumper to make the pump run all the time, if that doesn't help, the relay is fine.

Could your stalling be engine temperature related? Does it quit once it's warmed up? Will it start again sooner with application of the gas pedal while cranking? I don't mean pump it, just hold the pedal about halfway down.


To run right, an engine needs three things: compression, fuel mixture & spark at the right time. That's the basis for most troubleshooting although MB has laid out some basic tests in "tree" format. Lot's of info here, though you'll need to dig through a lot. Hope you've got a high-speed link.

Best of luck,

Prolly the fuel pump relay, I had the same problem. Yours just seems more severe.
But I would have it checked out first, this car is an expensive one to keep up. We just threw $1600 into ours in the past month...

[MEIN GEIL MERC]

Thank You Guys For Responding,nglitz Thanks Especially For The Link To Dakota's Mb Library.
I Replaced The F.pump Relay,and That Seems To Have Been The Culprit.ran It For Excess Of 15. Min Parked And Then Drove It About Ten Or So Miles And So Far So Good.also Replaced Rotor/cap And That Seems To Have Helped Out The Rough Idle Considerably.will Keep You Posted If This Has Actually Solved The Problem.thank You Guys Again,this Forum Is A Great Help For A New "old M.b." Owner! :d

[nglitz]

Excellent!