short and sweet went to give friend a jump to start car, drivewayicey took a while to get in but did came home shut off my blazer evrerything ok went out next morning fuel pump running first thought leaky fuel line nope ok,started right up, went for smokes came back shut off (ok) nope shut the door fuel pump running again wont stop running. Going to look at it in the morning .Any ideas what to look for. 89 fullsize blazer,350 tbi .

 

Most likely is a problem with the wiring where some wires are crossed...

 

Either the fuel pump relay has welded itself closed or the computer is not turning off the run signal. Try swapping the relay with the A/C relay. Otherwise pull the relay when parked so you dont burn up the pump. A cheap fix would be to rewire the relay to be powered from a manual toggle switch. It also serves as a deterent fornot so bright car thieves.