Stony123

Hello,
On Monday, after working and heading to my car in the parking lot, went to start and it would not turn over. Let it sit for awhile, finally turned over but as soon as I put it into first, it stalled out. Got a tow to my mechanic, where it immediately started up! They kept it 2 days trying to figure it out, no luck. It started every time they tested it. Checked battery/alternator, all that was fine. I trust them so I believe them when they say they tried everything. Got it back on Wed., was starting and running fine until this afternoon. Same thing! So right now there it sits in the public trans. parking lot. I'll head over there later on to see if I can get it going and at least home. The distributor assy. was recently changed in July.
Any ideas?