420 SEL won't start
 

Just bought a 1990 420 sel. Bought the car in South Carolina 3 days ago. Car has 155k on it. Car ran excellent on the way home(about 400 miles) stop and started several times. Took the car over to show my brother and when I tried to start it, it only cranked but would not run. After about 15 minutes of checking fuses and etc. it started right up. I drove about 1/2 mile and it stop dead. No sputter or anything it just stopped. Again after about 15 minutes of checking, it started right up. Ran about 10 minutes and quit again. Again waited about 15 minutes and start up. Temp is fine, tank is full. Car runs great when it is running. No hessitation or any problem. Just stops instantly. The last time I started the car I let it idle for about 5-10 minutes before it quit. And when it quit, it was just like you had cut the ignition off. The Ignition was still on and all idiot lights were still on. I have checked the relay with the fuse in top of it and the fuse was ok. Also checked the other fuses in the fuse panel under the hood next to the master cylnder and all were ok.:confused:
Any help would be appreciated.

Smack the fuel pump relay (one of two black boxes the size of a pack of cigs between the windsield and the engine firewall), to get you home. If that gets ya going replace it or resolder the PC board inside.