iron horse

when i try to start my 2000 xj it takes like two to four times to start. and i know its because a lack a fuel. spark and air is there. anyways i tested my fuel pressure and when i primed the pump i got nothing. i primed it twice... nothing. i primed it like 5 or 6 times and then got like 15 lbs but it was quickly dropping. then i started it and it took four times like usual. and pressure went up and was bouncing between 47-49 then shortly smoothed out to a steady 49 lbs. shut it off, and primed pump again, and there was no pressure again. any ideas of what this could be? could bad injectors possibly be the case? because my hard start happened when cylinder #6 was misfiring and i changed the injector and now its firing but its still starting hard and also idling a little rough. coincidence?

sorry for the long post. this is just frustrating me. thanks in advance!

Zj heep

Replace your fuel pump. I had the same problem.

iron horse

shoot thats what i was afraid of. but my jeep has 99,xxx miles as far as im concerned. would a fuel pump go bad that soon?

lngliv3

There is no set time life on a fuel pump... I am a certified tech i have seen fuel pumps die at as little as 5 k and have seen some that never die.... something to look at is the rubber hose between the pump and the sending unit if this is the style you have....... Chances are your fuel pump is about to pump its last drops of fuel......

tjwalker

If you buy a fuel pump assembly (and you should), do NOT buy an Airtex. Many parts stores carry them as a low price point but their reliability is extremely questionable IMHO.

I always buy a Bosch pump. Worth every penny more that you pay.

captainwoot

x2 i too am a licensed tech and couldn't agree more

iron horse

well i redid the test with my neighbor and the pressure jumps to 12 lbs and then goes down. but it goes down so quickly that by the time i get to the gauge and read it the pressure drops. so thats why i though there was no pressure when i did the test myself. what does the 12 lbs mean? is it as good as 0 lbs?

tjwalker

Whether it's 0 or 12, that just indicates that you are suffering from severe pressure drop, most likely because of the check valve on the fuel pump assembly. Failure of this valve is VERY common on 97-01 XJs

iron horse

so whats my best bet? bosch or oem pump?

413maxwedge

Buy the oem pump more money but 100x the unit.Most pumps die early due to poeple not keeping the fuel pump under the level of fuel the fuel keeps your pump cool thus extending its life. So keep your tanks at atleast 3/4 full and quit buying the stupid things not needed people just a little kick in the azz to open some eyes, no effence meant.(to keep the at bay) good luck

tjwalker

I have had equally good luck with either a Jeep fuel pump or a Bosch unit, and the Bosch unit will be about a hundred bucks less....

iron horse

ok thanks for the help everybody. my dads kind of in denial that its fuel pump and wants to replace all the injectors since its still idles rough and this whole problem occurred when one of the injectors went bad. so i bought the 4 hole precision auto injectors and hopefully that'll at least fix the bad idle. then we'll see what happens from there. ill make another post on how the injectors work if anybody cares to find out. thanks again everybody