I have a 1994 Oldsmobile 88 Royal that runs great, but sometimes when I stop and turn the car off and return a short time later, it won’t start. I hear the starter working to start the engine, but it won’t crank, sounding like it is getting no spark or no fuel. However, after letting it sit for 30-40 minutes, it starts. Fuel pump has been replaced. Some have said maybe it is a “crank sensor” or “an ignition module”. This chump is stumped!
Carry tools with you. Next time it refuses to start, pull a spark plug, and check for spark. If you get none, you know it is ignition related, not fuel related. Ignition modules and crank sensors can be tested. Best to test before dropping green on a replacement.