1991 M30 no fuel pump ground when warm

[TECH50]

I have a 1991 m30 that will start cold & run all day, but when shut off will not start for about 1 hr. It has fuel prime up ground but does not get constant run ground to fuel pump . Pulled pcm & cooled it in refrig when hot but still didn't help. Checked all power & grounds at pcm, checked relay and for spark & injection pulse. If I ground constant run ground at pcm for more than a munite it will start & stay running.