Had to tow my son's '88 740 Turbo wagon home last week (157k miles) .
Car died at gas station. It ran fine until fill up and then very rough after fill up. Then no start at all.
Now at home, car cranks and appears to fire, but on release of starter, it will not continue to run.
The car fires when the starter engages, and sometimes runs (well) for a few seconds after release of starter, hence problem is probably not bad gas or ignition.
Also, I jumped the ground on the fuel pump (under driver foot well on charge air overpressure switch). This caused the fuel pump to run continuously, but engine still would not run after release of starter. Hence probably not the fuel pump relay.
So what else? Mass air sensor, computer, ??
Thanks.
John S.