Startup problems after running - 97 C280 Sport

I would greatly appreciate any input, Thank You in advance!

---------- Has anyone had similar problems as the one I describe below, or have a possibly remedy?

I am having intermittent problems starting my 1997 C-280 Sport. Never cold, always after it has been run a while.

What happens is this: Every once in a while, after an hour highway trip, or stop and start jaunting around town, the car will not turn over. Instead, the starter will run about 5 seconds, then give up. If I wait for 5 or 10 minutes, it will turn over with no problem whatsoever.

I know it isn't a battery problem, the starter turns strong, but the engine simply will not fire up. Wait 5 or 10 mins, and it kicks like nothing was ever wrong.

The oil is clean, as is the radiator.

My radiator guage goes from 40 to 120, with 80 being the mid-point, usual running temp. I have noticed that the temp seems to be a little high when this occurs, but only a touch above the midline, MAYBE 90. After letting it sit a bit, as I said, it will fire up like gangbusters.

Is there some kinda built in thermostat protection that won't allow you to start the car if it is too hot, and maybe it is set wrong, or needs to be replaced?

I'm bumfuzzled!

Any input would be GREATLY appreciated, especially since I live in a rural area, and the closest M dealership is 100 miles away... trying to fix an intermittent problem with no local dealership is, well... :-/ !!

Thanks Much!

The battery is plenty strong. The starter is turning the engine with no problem.

When I said the starter will run for about 5 seconds, I was referring to the automatic start: per the manual, when you crank, the starter will continue to attempt to start the car for several seconds, then automatically turn itself off if it doesn't fire up. If I crank again, the same thing happens: It will turn the engine over, strongly and with no problem, but the engine will not fire up.

If I let the car sit for about 5 to 10 minutes, it will start up just like normal, with no problem at all. The temp guage is not particularly hot: normal running temp is 80, redline is 130, but it never gets over maybe 90.

There is no clatter, or any strange noise from the engine at anytime, it runs like a top.

When I am unable to start it, it seems almost as if there simply is no fuel being supplied.

It is particularly confusing that if I just let it sit for a few minutes, it cranks perfectly and purrs like a kitten!

(Thank You, and anyone else in advance for your insigts and suggestions!)

Art