Startup problem with warm engine (3.8L Olds)

[MarkB]

87 Olds Ciera 4sp auto
3.8L w/130K

Engine will crank and start when cold but after running for a few miles (~10-15 miles or 10-30 minutes) engine will not restart until it sits for awhile (sometimes an hour or more). It cranks and turns over but no startup. Fuel pump appears to be working properly. Engine is not overheating. No check engine codes.

Any general thoughts appreciated. Thanks.

[re-tired]

Welcome to the site . Check your basics first . verify spark ,fuel press and injector pulse. Do at time of failure and see whats missing , we can guide your troubleshooting from there.

[25 Fan]

Could be engine temp sensor telling it is cold