1990 LA 360 stops running when hot (help please)

Ddaddy said
Replace the ballast resistor first followed by the ECU box.

Most likely is the ballast resistor has failed and has a crack in the windings on the primary start circuit that becomes seperated with heat. However, the ECU could have a similar issue.

It’s cheap to just replace both and will likely fix it for little cost. 30 year old electronic parts are probably due to get replaced anyway.
Click to expand...
A 1990 Maxi Van will have a TBI and PCM... no ballast or ECU. I would start with the distributor pickup coil. Gets hot, pickup fails... It's a longshot, but if a local shop/dealer has an old pre-OBD scanner and remembers how to use it, it may help narrow it down a bit for you.