Warm start problems
You may have fuel pressure leakdown, caused by a defective fuel accumulator, or fuel pump check valve. I have also been told that injectors can also cause the leakdown.
I have a 1983 380 SEL that had the same problem. It ended up being a bad fuel accumulator ($80 part) which I was told is VERY common with a car that old. It now starts up like a new car, warm or cold. If it turns out to be the same problem, be sure to buy a BOSCH; the aftermarket ones look like JUNK.