About four times in the last six months, our 87 300E has intermittantly refused to start when hot. The engine cranks, but doesn't catch. It never seems to do it with any consistancy - once after sitting for about an hour and a half, took about 15 min of intermittant cranking to start. Another time, the car sat for about 1 minute, and took about a minute of cranking to start.

From searching previous posts, I suspect that it may be a fuel pressure leakdown, resulting in vapor lock, but i don't understand why it only seems to happen occasionally, and never after the car sits for the same length of time (granted, my diagnostic abilities are somewhat green)...

thanks,
anthony