190E 2.6 Stalling - Need help

Here's a strange on for you. My 1991 190E 2.6 stalls under the following conditions, and ONLY under the following conditions. Very difficult to troubleshoot!

Must sit for at least 24 hours without running first.
If driven everyday, problem never occurs.
Always happens on a Monday, because I don't drive it on Sundays.
Always happens after about 3-4 miles, after starting and running 100% perfect for the first 3-4 miles.

Starts stumbling and won't idle. If you don't keep the RPM way up, it will certainly die. When it dies, it won't start back up. No smell of gas when trying to restart. Cranks strong, but won't go.

After about 20-30 minutes of just sitting, starts up fairly easily, clears itself up, and runs 100% normal again.

Will run 100% normal everyday until the next time you let it sit for over 24 hours, then will do the same thing again, everytime.

Help! I don't want to take it to a shop like this, because when it's not doing this, which is most of the time, it is running 100% great and normal.

Any ideas?

Thanks, Wayne

[Chamorro]

Fuel filter?