98jeepcher

In the past few days my 98 xj has been acting up. I go to start it and it spins over like normal but takes longer to start up. I have also noticed just yesterday and today, when i go to start it up it will kind of stumble like it is wanting to start, then start. It will run fine and all, but after running it for a couple mins and turning it off it will start up just fine. Im thinkin maybe Fuel Pump? I am gonna run a fuel pressure test on it tomorrow. My question is what should the fuel pressure be at. Any suggestions or questions just let me know. Thanks

98jeepcher

No one?

Cearl

i was going to say maybe check the battery or the starter, id also check the alt. just my two cents
(mine does the same thing :P just have been too lazy to check i have a feeling it's the battery though)

NorCalJeep

sounds like the fuel pump. there is a test for called poor mans fuel pump test.

98jeepcher

Forgot to mention i checked the voltage on the battery yesterday. Thanks though.

Cearl

alrighty, so yeah i'd go with the fuel pump. how does that test work?

98jeepcher

Lol okay and how might this work.

98jeepcher

I also forgot to mention today i cycled the key three times and she started up just fine. As in cycled i mean turned the key in the on position for a sec then turned it off.

navy digital

got my jeep this was the first fuel thing i dealt with. the extra 10 seconds of crank time isn't good for the starter, and cycling the key over and over wears the ignition switch out. so unfortunately your going to have to drop the tank and change out the fuel pressure regulator. its easy but plan ahead. use some wd 40 or pb blaster on the threads holding the tank on before starting this project. i snapped one off so my buddy welded it and fixed it. also get some screw type hose clamps for the fill hoses cause the oem ones are junk.
save your computer also buy disconnecting the battery first.
good luck. o and fuel press should be from 38-60 psi depending on pump, filter, fuel type and temp.

Radi

The anti-drainback valve is leaking. The fuel rail loses pressure over time and you have to re-prime it by cycling the key (which runs the fuel pump) a couple of times.

It's harmless, it doesn't mean the fuel pump is on it's last leg. You can replace it (valve is part of the fuel pump ***'y), or just cycle the key once, maybe twice before starting.