Any advise would be appreciated....

Was driving my 91 240 sedan (155,000 miles) and car died in slow traffic, rolled to center median, tried to turn car on and it started again, got back into crawling traffic, cut out again, this time , turned onto side street..and
started up again.. then drove side streets 2-3 more miles without incident, picked up baby and went back home (11 miles), hesitated to cut out again while going 30 mph, but did not... have about a 1/2 tank of fuel (read it could be fuel pre-pump???), never any problems before of cutting out, has new oxygen sensor, plugs,wires, cat-converter.. day was not real hot, mid 70's .. going to drive to work today and see what happens.

When was the last time you replaced or resoldered your fuel pump relay? It's behind the passenger side knee bolster. If you are sitting in the passenger seat and lift your right foot up, you will be pointing right at where it lives (though of course you won't be able to see it unless you take the knee bolster off).

Also check the 25 amp blade fuse that lives between the battery and the ignition coil, way out on the side of the engine compartment. Pull it out, clean up the terminals, replace it if it really looks bad, and when you do replace it put some dialectrical grease on the terminals. There are other things that could cause you symptoms, too. Next time it happens you might try disconnecting your AMM too see if it runs better. If it does, time to start thinking about getting a new AMM.

Do you know how to pull the codes off of your diagnostic computer? You should probably do that first thing, as it will probably tell you what the problem is. You can find out what the codes mean in your Bentley manual (you do have one, don't you?), or if you don't have a Bentley you can post what the codes are on this board and somebody will help you figure it out.

Definitely some good ideas!

"Also check the 25 amp blade fuse that lives between the battery and the ignition coil, way out on the side of the engine compartment."

Scorch, I thought about the 25 amp blade fuse too. Ask me how know about this problem....However, I believe the 1990 models were the last year to have them.

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Jim 90 244DL 243K

You are correct. The 91 doesn't use this fuse. Instead, the 25A fuse is in the main block. (Think it's #1.)
My 91 needed a new fuel pump relay the day after I drove it home. Figures, huh? Glad it didn't die on the highway at least. Good place ot start, but often causes no restart.
I think it's more likely the crank sensor (aka rpm sensor, aka impulse sensor) that looks at the flywheel position, giving the input to the fuel and ignition computers. It's a $40-ish part, on top of the bell housing in a lousy location but is essential and likely to be going bad in this age of automobile. They can be intermittent.
Also check the connections at the AMM in the LF fender. Do not disconnect or reconnect with the key on. The pins can make poor connection in the 6-wire plug, and give a fault like this. It *should* come up as a Check Engine code, but half the cars have no light in there now due to the way certain mechanics "fix" things.

Worth looking at in any case. New AMMs run $300 or so. Used ones can be had for $50-100. The part number ends in "016", and that's how they're referred to in parts books. Earlier cars took the "007". Good luck!
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Rob Bareiss, New London CT ::: '87 244DL/M47- 230K, 88 744GLE- 220K, 82 245T-181K Also responsible for the care and feeding of: 88 745GLE, 231K, 87 244DL, 239K, 94 855GLT 189K

I tnink he "25 amp fuse" got replaced by a 16 amper in fuse position #6, starting in '91. Definitely worth checking contact conditions.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Please check for ECU codes and post.

THANKS FOR ALL THE ABOVE ADVISE!!!!

I continued to drive the car to work and back and no problems either way..
( i dumped 2 bottles of carb cleaner in tank b4 leaving to work)

I checked fuses inside car, all ok, checked for faulty codes, there were
non. My check engine lights comes on at start and turn off as normal.
I replaced the fuel pump relay about 1 year ago...because car would not start
when leaving work on a really hot day.. new relay took care of this problem.

Hopefully all is ok but one thing that stuck in my mind, when it died out
while driving at 30 mph, if "felt" electrical. Would the crank/rpm sensor
give a faulty code??

One thing i did not mention earlier thinking they were not related, at
time of engine problems I had no brake lights(do not know if it just happened or was like this prior). Another car at a stop light informed me of this.. so from there (was daylight) I used my night lights by turning them off and on upon stopping. I came home, got on this websight, and read info on how to diagnose and then fused the 3 prongs on the "bulb failure sensor" which worked. Car ran fine today, do not know if related.


Thanks again for all the advise, can't say enough about how it has helped
me.

A couple of simple, cheap ideas:

Have you soldered or replaced your fuel pump relay? If not, that is a distinct possibility.

Also check and clean fuel pump fuse, and wouldn't hurt to do all your fuses while your there for that matter...

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Jim 90 244DL 242K

if you have no idea of what it could be, if everyhtign else has been looked over (i.e. fuel filter, air filter etc.) then I'd probably recommend just taking it out for a really good and healthy hard drive. In many cars that I've had, sometimes after I've let them idle for long periods in traffic, or not driven them for a good week or so, they get a funny common idle problem, and sometimes stall out, or (as in the case with my 88 325is) cause the "check engine" light to come on. If there's nothing that I can possibly think of (after givin gthe car a good once-over), I take it out to the highway and run through the gears very briskly, and swiftly. If the problem has not remidied itself, usually at this point it's easier to diagnose the problem (as other problems may surface).

My mechanic told me this after his brother who was a mechanic in England for MB, had owners come to them with relatively new MB's ( in the early 80's and late 70's) and they would be running terribly. As a result the 1st thing the mechanics would do is take the cars out for a hard drive. Usually it causes the carbon deposits that may have formed around the exhaust valves to get burnt off and get the engine running more efficiently again. Usually this was the case with Dr.'s who were usually older ppl. that hardly took ther cars out on the highway. Instead they would sit in traffic, and idle, and not get driven he way they should be.

good luck, and let us know how it goes :)