Crank, no start 89 XJ
Hello yall, new to posting this stuff but I have a 89 renix Cherokee with 4.0. it cranks with no start. Replaced: injectors, distributor, cap/rotor, plugs, crank sensor, fuel pressure regulator... It has good fuel pressure( even better with new fuel filter). It has spark to all cyl's, TDC was set and just can't figure this out. I would like to have it running for sons 16th birthday in a few months. I'm sure I'm leaving out some stuff I replaced but I'm stumped on getting this running... Thanks for reading.
Last edited by Boozehound; Dec 4, 2016 at 12:04 AM.
CF Veteran
Joined: Dec 2015
Posts: 2,139
Likes: 93
From: Syracuse, NY
Year: 1996
Model: Cherokee (XJ)
Engine: 4.0L
If you have confirmed spark to all cylinders, then the next thing to test is that the fuel injectors are actually being commanded to fire. (fuel pressure is good, but next is to make sure that it is actually getting delivered to the cylinders).
Timing could still be an issue, but even if timing was off, I would expect you would get some sputtering, and random detonations if fuel was actually getting in.
If you find that the fuel injectors are in fact firing, a stuck/closed IAC (Idle Air Controller) could also be a culprit, but this can usually be tested by feathering the throttle pedal a little during start to let some air in.
(I don't know 89s well, so I'm assuming that it has an IAC or similar component).
Timing could still be an issue, but even if timing was off, I would expect you would get some sputtering, and random detonations if fuel was actually getting in.
If you find that the fuel injectors are in fact firing, a stuck/closed IAC (Idle Air Controller) could also be a culprit, but this can usually be tested by feathering the throttle pedal a little during start to let some air in.
(I don't know 89s well, so I'm assuming that it has an IAC or similar component).
Purchased Jeep not running for my son when he gets a license. I wanted him to appreciate his first vehicle not get keys and destroy it. I will check command to injector. Spark, fuel in rail, and tach needle moving should rule out computer if I'm not mistaken. Unless the computer is not commanding injectors.... thanks, so far guys.
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Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
The books are wrong, #1 is at 5:00 viewed from the side......Holding the petal on the floor will cut off fuel and help clear it if it's flooded. That brittle little tube from the TB up to the MAP is crucial. Any crack/leak, or blockage will cause real trouble.
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Appreciate the help but wouldn't that sputter while trying to start or stall after starting... this is just a solid crank with nothing..... tomarrow I'm picking up a noid tester for the injectors... I'll keep ya posted. Thanks again.
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Confirm.....
Well, I was at work today pondering this issue and said to my self, "self, are you sure you really redid timing at TDC". So I came home and put cylinder 1 at TDC and looked where the rotor was and it was 180° off. Re did it and sure as **** it fired up. I want to thank everyone for their input and help on my problem and my mistake. Thank you.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Well, I was at work today pondering this issue and said to my self, "self, are you sure you really redid timing at TDC". So I came home and put cylinder 1 at TDC and looked where the rotor was and it was 180° off. Re did it and sure as **** it fired up. I want to thank everyone for their input and help on my problem and my mistake. Thank you.



