1967 250SL undriveable when warm

[vrsmith]

We drove the car for 60 miles without incident. Suddenly the
engine started shaking violently at a stop light and was very
difficult to get going. The dead stop idle was OK but it was
difficult to rev it up. It stumbled, back-fired and nearly quit.
If I got the revs up to 3000 or better, it smoothed out and
could be driven. I had to aim the car at green lights, (3).
I would idle at the side of the road near a light, coax it up
in RPM and then keep the revs up to go through the light.
It is a fuel injected, automatic model.
I got it home without further serious incidents. I am now
waiting for it to cool to see if it is heat related. The car was
not running hot at all. I tried to shut it off and it ran-on for
a bit which seems to me that it was flooding. Any ideas to
consider would be great. I will be calling the mechanic asap
so I may have more info soon as well. Thanks in advance!

[Arthur Dalton]

You may have a leaking CSV valve .. It is the cold start fuel enrichment device on the intake . There is a 6mm hex cap on the side of the valve..take that off and see if any gas is coming out that port with the key ON, engine OFF.
If yes, then it is leaking raw gas into the engine [ could be stuck open or dirt keeping it open]

Could be many things , but I would start there as that is a common problem on MFI..

[hill]

VR
Mr. Dalton gave good advice. If you want more info try http://www.sl113.org/forums/default.asp

I checked thr forum rules they don't sell parts.