I just bought this vehicle about 2 weeks ago. New battery, distributor, and had two keys lazor cut for it. Because the previous owners had lost the originals. At first I was having problems with it occasionally not starting. But after waiting a while..it would eventually turn over. But this last time..I was going around 75 mph on the interstate..when my vehicle decides to suddenly quit running! The motor shut down. My interior lights on dash came on. Engine quit running. As if the key was put in the “on” position. I don’t hear the fuel pump coming on when turning the key on. But fuel pump is testing good. Changed fuel pump relay, even straight wired the fuel pump. Nothing. What could cause the fuel pump to not come on and would cause motor to quit running at 75 mph?
Step by step no start diagnostics troubleshooting chart – This should guide you through the proper steps needed to source the cause of the problem. Looking at the wiring diagram of the fuel pump circuit it would appear as the only thing left would be the computer or wiring connections. Check the ground and ECM fuse first. If you can apply battery positive and negative to the pump and it comes on, then the pump is good. If it does not come on, replace the pump.
Have you tried spraying starting fluid in the air filter to see if it will run. That is an easy way to see if the only thing the engine is missing is fuel and not spark also. If it is missing spark too, i would lean toward an ECM issue.
Fuel Pump Wiring Diagram 1999 Nissan Pathfinder
