XJwonders

the check valve is shot causing the fuel to go back to the tank when the engine is shut off.

Mattloz

Well some is normal but my issue is the car is not starting at all I get 39-40 psi when I turn the ignition on so my fuel pressure is technically good for it able to at least turn on I just need help on why it dosent start I was able to get it to turn on once and spudder a few other times

Also I talked to my technician and he said fuel pressure is good and some pressure is lost to a certain point I only dropped about 8 psi after 12 minutes

Mattloz

Ok guys well I got home and took some break clean with me and sprayed some into the throttle body well guess what the jeep turns on and reeves to about 1500 rpms and turns off ( obviously) but why isn't it turning on if I have 39 psi and injector pulse and I think my injectors work because I used my power probe and felt then click on and off sooooo what's next???

JeepJeepin

Did you try whacking the gas tank when it does that?

Mattloz

No what would that do? I have a feeling my fuel filter is clogged and not supplying a steady steam of gas

Mattloz

i have a update guys well my jeep turns on now takes a few seconds to start but what i did to fix the problem was change the fuel filter lol now the jeep turns on and stays on lol

cruiser54

Wow. What a concept?

Performing normal maintenance first................

Mattloz

yea i know its always something stupid i had checked everything including fuel pressure test and i was good on everything. so i tried brake clean and well it stayed on until i didn't supply enough brake clean to keep it alive so i knew i had a fuel flow problem so i did the filter because its easy and cheap. lol

but it does take about about 5-10 seconds for it to acctually turn on and it also seems less powerful and responsive as my other jeep mind you its the 4.0 ho im guessing its the renix slow erra with its small throttle body compared to the 91

by the way do you have anytips on how to check the 4x4 because i put it in 4hi and i tried to pull my 17 foot boat out on grass and was spinning my rear tires(rear tires are ****ty no tread at all completely bald) but i was on 4 hi and i wasnt moving anywhere, when i turn the drive shaft by hand(car off) and shift the leaver it engages i think its the vacuum actuator or the fork in the axle do you have any test for me

Mattloz

ok second update after about 4 hours or so of sitting in the garage in 80 degree weather i went to start it and well i just cranked and cranked so i stopped pulled out my trusty brake clean squirted some inside boom it fired it died put a little more fired again then struggled to stay on but it did, then smoothed out turned it off waited 10 seconds and turned on again. But earlier today i was driving it around the house and would turn it off and on and never had a problem ( didn't sit of for more that maybe 20 minutes) it has a cold start issue (if that exist)

also i read more about the 4x4 stuff and non of my light turn on( do i even have lights in a 1990 jeep cherokee) i do have vacuums actuated axle, and diag notes will appreciate it

cruiser54

You have a fuel delivery issue.

Get that addressed first.

Mattloz

you think fuel pump pickup screen may be clogged

XJwonders

we aren't gonna think anything. We can't see your jeep from here. You gotta take a look at all possible causes.

Mattloz

yes what confuses me is that once its on it runs and i could turn it off and 10 minutes later it turns on im just confused

Mattloz

ok gusy i have a update well i talked to my mechanics that i work with and we go between the fuel pump and the distributor, well before i left work i spoke to the engine guy, well he mention he knew about a problems with jeeps not turning on cold. well long story short he told me to check my coolant temp sensor ( i didnt have mine installed) i got home and out in the coolant temp sensor and guess what..... it freaking turned on, are you serious i was going crazy over a freaking sensor that i didnt know could effect a no start issue well yea it turns on now