hello all new to the forum but been lurking in the shadows for a while now ... i have a 97 grand cherokee with the 4.0 it has 240k on it the thing will crank for about a good min before it will start .... runs a little ruff then your good to go ... i looked for a regulator on it cant find one took the cap off the rail and pressed the valve in and got nothing from what i have read here it could be the little check ball in the tank ???? or injectors leaking down ... how would i go about checking the injectors ... ??? take them all out with the fuel rail key it up see if one leaks ???

thanks a bunch ...


Regal

 

How easy will it start up if you cycled the key on/off 2-3 times before starting engine, keep key on for a couple seconds before turning back off to allow the fuel pump to prime.

You could pull up the injector rail and with injectors still in the rail to test for injector leakdown. Injectors would not be my first guess, but this test step is fairly easy to check.

Your fuel filter is mounted on top of the fuel pump (top of fuel tank), the filter also serves 2 other functions, it regulates fuel pressure and has a check valve in it. There is also a check valve in the outlet end of the fuel pump. Though it sounds strange that both check valves are failed, but if you wanted to try the cheap route then replace the filter assy and see what happens, probably due for a filter change anyway. The only problem with replacing the fuel filter is you will need to drop the tank, which is the same procedure to replace the pump.

 

i had the same problem and i had to replace my fuel pump it was easy to do and will only take an hour or two my regulator was shot and it only took a few mintes and all of the gas would leak back into the lines.My suggestion is that you buy an oem pump and dont waste your time with aftermarket ones. I went through 3 airtex fuel pumps and finally got fed up and bought a stock oem one. If you do decide to cahnge it dont forget to let the pressure out of the line on the shrader valve on the fuel rail.when you do this make sure you put a paper towel over the valve when you release pressure from it because gas will come out as well, have fun

 

did u figure out the problem