negative. same issue...though now worsening.

now at idle, once warm, it will stutter, recover, stutter, recover. according to the economy gauge its just dumping fuel to recover, why it is losing fuel i have no idea.

now the battery is junk, so today i have it hooked up to a charger, started it, then went to disconnect the charger and it began to stall, hooked it back up and it idled fine. is this an alternator problem? or some massive electrical drain somewhere? once idling, if you turn the headlights on, it stutters. could that be the extra load on the engine via alternator, and therefore the same original issue?

this only takes place while warm.

also, alternator tests 13.74 volts at idle and maxes out around 13.80 at higher rpm.

another thought was plugged cat. there seems to be a leaky joint below the exhaust manifold and not much exhaust coming out tail pipe. could it be excessive back pressure, or exhaust leak?

anyone?

hello,i see many great points,have any of you checked for a defective electro hydraulic actuator,its designed for helping with cold starts,it can make the engine run horrible when its defective,hard starting,engine bogging down,popping in the plenum,backfiring,a strong smell of unburnt gasoline,try unplugging the sensor its located on the rear side of the fuel distributor,its a black box with 2 large flat head screws in the top,with a 2 prong electrical connector facing the fuel injectors,please becarefull when loosening the screws,this actuator is under high fuel pressure.release the fuel pressure by loosening up the cold start valve fuel line on the fuel distributor,make sure to have rags to absorb the leaky fuel,there wont be much at all,check the continuity of this sensor,it is a very costly new sensor up to $350.00,you can buy a quality used one for $50.00.good luck.

What is it with these mercedes and problems when warm . Did they design them to run in the cold even out of gas.

Mine runs when warm , but wants to be coddled. When cold it thinks its a race horse .

Darn Benz designs them for the freezing German winters . Sorry for venting but I see a lot of unsolved problems with warm Benz's.

Did Treetrimmer give up . I have been trying for 2 months now . Hang in there everyone . Pray for an Ice Age

Until the engine is warm and the o2 sensor comes on line, I don't believe any electrical components affect the fuel distributor. After that, it's all eventually thru the EHA. The cold-start injector might be the exception.

__________________
2012 E350
2006 Callaway SC560

tried this one today because it seemed to match. unplugging the sensor is the test, correct? after that it should clear up? i did and there was no change...

The EHA is effectively "unplugged" when the engine is cold. It does not come to life until the engine is in closed-loop mode.

__________________
2012 E350
2006 Callaway SC560

I'm not convinced of this. In fact, when my W124 (with 103 motor) was still quite new, the dealer replaced the EHA under warranty in response to hard cold start symptoms. Cleared up the problem. Moreover, according to the FSM, the purpose for the EHA is fuel adaptation in all of the following conditions:
(1) start enrichment; (2) post-start enrichment; (3) warming-up; (4) acceleration enrichment; (5) full load enrichment; (6) decel fuel shutoff; and (7) Lambda control. Pretty much everything involving proper fuel management.

__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't

The EHA receives no signal from the computer when the engine is first started cold. Have a look at the lambda (or the voltage to the EHA). You will see it come to life after the O2 sensor is warm enough to provide some information for the computer to work with.

Or unplug the EHA. The car will start the same when cold, EHA unplugged or not.

The system is basically mechanical. The EHA only fine tunes the mixture. The engine will still run without the EHA's influence. It's a pressure fuel-injection system, just like on airplane engines - which have no electrical input at all, BTW.

__________________
2012 E350
2006 Callaway SC560

It pays to check the normal wear items first- even if they look ok....I took a gamble and paid $800.00 a week ago on a '92 190E 2.6 Sportline 5 speed that had the dreaded "when cold runs great, after 10 minutes running and warm, dies and won't restart until cool" syndrome. I had noticed the PO had spent a bunch of cash replacing virtually all the items that are typically suggested in the various MBZ and 190 forums...ignition control unit, crank pos sensor, OVP, coil and even the computer- all to no avail and had ultimately given up and just put the car up for sale as-is. The one thing I noted that hadn't been replaced (and occasionally mentioned in the forums as a culprit) was the simple cap and rotor...

Today, with another $80.00 invested in a cap and rotor plus 20 minutes of my time, it's now running perfectly...the best $800.00 car I've ever lucked into! The other clue to me was that when it was warm and wouldn't restart, it would crank in kind of a "notchy", irregular way (that it did not when it was cranking cold) and that made me think it was ignition and perhaps cap/rotor related. Hope this is helpful info...

J.G.

I had about the same problem on my 89 300e. Found it was a bad connection to to O2 sensor under the carpet in front of the passenger seat. twisted the connector and now runs like a champ.