How can tell if fuel pump is bad?

Yep, that's about it...I have a 97 XJ 4.0 and just trying to figure out if my fuel pump is going bad...how do you figure that out?

Thanks,

Chris

does it start at all? whil cranking, you need to probe the fuel pump feed wire at the fuel pump connector under the jeep, over the rear axle. if you have power and no fuel pressure then the pump is bad. if you dont have power then its another problem maybe the relay or something else.

Try cranking your engine for a minute, or just turn the key on but not to the crank position. That should kick the fuel pump on to pressurize the system for engine start. Inside the engine compartment you should see the fuel rail. If unfamiliar it is a metal tube that runs from the front to back of the engine with six wires going into it, all six injectors coming out of it. There should be a pressure relieve valve on it. They will look like the plastic caps (maybe aluminum) that cover your valve stems on your tires. Unscrew that cap and depress that little pin like you would to let air out of your tires. Place a rag under to catch the fuel that comes out, and watch your eyes (safety glasses). If the fuel sprays out then the system was pressurized and the pump is working. That just means it is building pressure, but doesn't necessarily mean it's putting out enough pressure to keep the engine running. I'm sure there is a guage that hooks up to that little port to measure the system pressure.

Had this happened to me.. sputtering after running for an hour, gassing it get up hills or inclines will set it off, running hot/almost overheating, back firing, runs real bad after 2.5k RPM, no check engine codes..... weak fuel pump, swapped it out and it was all good after that.

good luck