Ok. I am having a similar problem to several other members. Random stalling of the engine, can occur at idle, while cornering or at steady speed. No warning, spluttering etc. Just sudden and total engine shutdown.

History: Can has rarely run smoothly in the 7 years I have had her. One fuel pump failed about two years ago. I went through three mechanics who failed to diagnose the problem since fuel pressure only declined at 4000 rpm when under load. However to keep car running the CO mixture, Duty Cycle was turned way rich. After I found and replaced the bad pump the car ran wonderfully until about two months ago when the stalls started.

Usually the car restarts after a stall except when really hot. Have since corrected the duty cycle to 50% and restarts are very easy.

I do not think issue is OVP related - I pulled OVP fuse and engine speed increased and no stall. Idle air valve is operating and EHA sits at 0 ma. Have pulled on just about every wire and tapped every relay but to no effect.

Where should I look next?

Thanks,

Ian.

do the lights go out when this happens? is this an electrical thing? when you try to immediatly restart it what happens? It doesn't immediatly want to go, you have to sit around for a while? But when you turn the key immediatly after a stall are your warning lights etc. coming on?

cdt

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2002suzukiGSF600S
1985 190e 2.3

When the stalls occur the radio etc stay on. If it is an electrical failure it only seems to effect the engine. Yesterday evening I ran the engine to check the mixture setting and to shrink on an exhaust repair kit, I had a 1/2" hole on top of the pipe where it enters the rear muffler.

Noticed that she is running mush more smoothly but was putting out noticable water droplets for quite a while and also some white smoke, which I have not noticed before I corrected the over rich condition (It was also cold for down here in Houston). I am almost wondering if the engine is burning off some oil, carbon or other gunk from a previously misfiring cylinder, the O2 sensor or elsewhere in the exhaust system. Did not smell of antifreeze or real oily for that matter and there is no water in the engine oil etc. Coolant level is fine, but she has historically consumed some oil about a quart every 750 miles or so. She does drip a little from the top of the timing chain cover which gets blown along the side of the block.

The only other thing I did was add a can of Restore which seems rto have increased the vacuum on the hose port from the air cleaner to the valve cover.

Ian.
'89 190E 2.6
'90 Mustang GT 12.7 sec quarter mile.


What really gets me is that my 90 FORD Mustang GT is a much more reliable vehicle, one clutch, an alternator and the occasional cleaning of the idle air valve and she pulls 285 rwhp, with some minor mods and turning all done by yours truely. Oh I did break the driverside engine mount, which amassed the Ford Motorsport guys, one hard launch too many.

I have the exact same thing happen with a 88 560SL. Only the engine dies, and it is a complete drop out, no sputtereing. As if the ignition just cuts out, or the fuel pumps have stopped. How do these cars stall if the fuel pressure is too low? Do they sputter and hack, or do they just die? It would help to know which system to look at.

tony

Well this weekend has seen some progress. The engine has seen some serious running time, albeit stationary. I wondered if the smoke was due to a head gasket leak, so I added some antiofreeze to the overflow tank and ran fired her up. Sure enough she overflowed out the added fluid so I am sure that the cooling system is completely full. I added an oil thinkener and within 10 minutes the smoking was gone. She is still putting out quite a bit of water so i will try a water system sealer in the next day or too.

I have noticed that the CO mixture/Lambda correction reading has been getting progressively leaner and I have had to adjust it a little back towards rich to get it back to 50%.

Ian.

The original symptoms of stalling at ramdom times are exactly what I have had for the last year on my 190E 2.6 1990.

I have taken it in to the local Mercedes dealership who have claimed to check the Lamba, set the idle, changed the Overload Relay, new distributer cap and rotor, new plugs, now they have asked me to consider the MAS as the next step and a few more costly items...

I have left it with them for weeks, (good thing I have another car), they claim it never happens with them, etc.

I have just discovered that they NEVER changed the OVP! (it just happens that I was looking at a blown fuse and found my original markings on the OVP!)

My question is this: Could this stalling be simply the result of the bad OVP after all?

What else could this be? It normally cuts out when I am turning, say into a parking lot (mostly to the right handside), or in stop / start traffic coming to a stop suddenly...and now the weather is warming up, it is becoming a more frequent event again...winter was better.

Thanks,
Don

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Don

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'90 300SL
'90 190E 2.6
'87 300TE (gone to car heaven)
'84 190D (passed along...still in the family and used on a daily basis)

OK guys I found the problem. The one causing teh stalls that is. I pulled the cover off the fuel pump relay only to discover that two of the solder welds had come lose. One was the output connection from the actual relay switch. Carefully resoldered the connections, tested and reassembled. She has not stalled since. Also the smoking went away and all fluid levels have been stable. Also noticed that she runs better on mid-range gas (89 octane) although the idle is still a little lumpy. She will get up to about 90 on the freeway and seems to be holding together. Ironically the Mustang started acting up and after struggling home I switched out her sealed fuel pump relay ($11) and she is now fine. What are the odds on that?