Fuel Pump

98 Jeep Grand Cherokee 4.0l

My neighbor just installed a fuel pump on his Jeep and when you first try to start the jeep it won't start up, If you leave the key on and let the pump pump fuel up to the front it will start right up. What could cause the delay for the fuel getting to the injectors? Thanks for any help

How much time is considered a delay ? Some times 3-10-sec is'nt much. Does it happen right after running and then restarted ??The pressure might not be holding and bleeding back also check for any restiction points. A pressure guage will let u read both. Chris

Your problem here is kind of generic, but you might want to know there is also a part of the AF that specializes in the GRAND Cherokee (Yj and Zj models). This part of the AF is usually the XJ model forum.

The above thread is good advice though, wait for the fuel pump to pressurized the rail before attempting to start the engine. The reason for this happening is the check valve in the fuel pump is leaking and the system is depressurinzing when park for a long period of time. However, to change this check valve and fuel pump requires draining the fuel tank, removing or dropping it down and replacing a somewhat expensive part (not to mention the labor involved). I would just use the "work around" that was mentioned earlier, wait for pressure to build before cranking.

Best regards...

Hey, Thanks for the replys. I'll have them check the pressure. Thanks