advice on running woes, help needed Options

[enf2232]

Back story, short(?) version.
1.7 engine was recently rebuilt. New case, pistons, and cylinders. FI and other components brought over with new injectors and a used wiring harness with ECU. After bringing it home I drove it to work, 20 mi each way and it ran fine. When putting it away the spring popped off the accelerator. After fixing that it went for a very short drive with no hiccups. Then set off to work again earlier this week. Started and ran ok (cool morning) but stalled when I had to stop for a school bus. It then would not restart. Turned over but would not start. Towed home. After sitting while at work I put a trickle charger on it to be sure the battery was ok. Again it started ok but when it did stall it did not restart. Pushed into garage and attached trickle charger. Today started it and was going to let it sit and idle for a while. When I checked on it it had stalled and did not want to restart. Let it sit, put trickle charger on to be sure battery was charged, and waited. Went out and it started ok and I sat in the car while it idled. Did ok for a couple of minutes then I had to keep gas on it to keep it running. I let it stall and again it does not want to restart after running a bit.

Any suggestions on what is going on, what to do next, or directions for repairman?