VASQUEZ171

I'm having all the same problems with my 99 but mine accelerates on it's own sometimes

Drewjharper1900

Well as i was driving it today it seamed like it had gotten worse. It was stumbling when i put it into drive when i first started it and i lost my power steering for a bit. Gona take it to my mechanic wednesday to see if we can figure it out.

sik_xj

I am having the same issue, to an extent.
Let me know what you find out because I have been dealing with this for months and replacing stuff that never seems to help at all.

Drewjharper1900

Im betting on either a failing fuel pump or a failing electrical component.

VTJeep

I had a ton of **** floating around in my tank.. Some how.. Either way, cleaning it out helped reduce a lot of my hesitation/popping at manifold issue. But it wasn't the cure. I've run the gauntlet one this one, too... New everything.. What's really odd is if I to to my guy and get the codes cleared, the CEL goes away and it starts and will idle fine, but buy the time I get to the road (~1/8 mile) it will act up; hesitating, backfiring at manifold. Going WOT will make it go away. After this the CEL will reappear, sometimes within 30 min, and it will run like a champ. Nice smooth idle, good acceleration and IMHO nominal mpgs.

Super stumped. But I'm gonna post the **** like crazy WHEN I figure it out!

Drewjharper1900

Just did a fuel pressure test. Only had 20psi. I think that may be my problem..... haha Grabbed a new pump and gona put it in sometime today. Should fix some(or all) of my problems.

Drewjharper1900

Put the pump, jeep is happy again!

VTJeep

Sweet man! Glad it worked!

jeeponblocks

Might check your camshaft position sensor!!!

Dcoy

Hey what's needed to check the pressure in the fuel rail? I have a very strange misfire issue and checking the pressure wouldn't hurt. Strange thing of mine is that if I shut my jeep and restart it will run fine..... until it cools down

Drewjharper1900

A fuel pressure guage.

eggdashure

What kind of MPG's were you getting prior to replacing the fuel pump? I have two of the symptoms you describe...rough idle and loss of power. I've done most of the things you have:

784 Injectors
Hood Vents
Cap, Plugs, Rotor
(Cat on order)
Replace cracked manifold
O2 Sensors

Did your mechanic test fuel pressure or did you do that yourself?

Thanks!

Drewjharper1900

I was gettin 11.5 city and 17 highway,

and my mechanic did the pressure test.