1988 300E idles around 1000 rpm when things are good. Here's what happens, though. If the morning is cold, it starts right off, I mean immediately. But, sometimes (and no rhyme or reason, here) when I get to a stoplight or sign, the idle will decrease to around maybe 750 rpm and then it will die. Starts right up again, but then for some time I'll have to basically either put the shifter in neutral to keep the revs up enough so it won't die again, or left brake and rev it a bit when I stop so it doesn't die. But, after a while, it regains the 1000 rpm and it's good again.
The engine temp doesn't get higher than normal, oil pressure looks okay, car runs fine all other times. Good acceleration, etc.
???
Thanks,
Tom in Tulsa, OK

I think 1k is probably too high, that 750 is the proper idle. That's where my m103 idles, and it's rock steady and smooth as glass. No hunting, no stalling, no missing. Pull any stored codes and see what's there. If you haven't performed basic maintenance on the car, maybe now's the time to get to that. There are numerous possible culprits. It's probably just undermaintained.

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