Starts runs sits poor start?

My 91 3.0 that sat a few years until I got a hold of it then I put in a ECU and IAC to get it going. It starts well cold it has a fast idle. If I unload it while it’s turned off it starts right up say 10 minutes it starts fine.

If I run to town and grocery shop longer then 10 minutes it cranks but no fire. To me it seems like I leaking fuel into the throttle body. Yesterday I drove a couple of miles shut it off for 30 minutes and took a while to get it going with starting fluid . Cranks and cranks not a bump in the cranking at all?

If it sits overnight it fires up no problem starting just turn the key boom it’s running. I tried to lower the idle but the cables loose so it’s on fast idle all of the time.

Any clue where to start I don’t want to burn up my starter? It’s getting a total rebuild this winter top to bottom.