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supertubesocks
August 26th, 2011, 10:38
Here's the quick version.
I have a 91 xj with 4.0 automatic 231j tcase.

The jeep was sitting for years and i just got it running. Then was forced to rebuild the engine. We got the engine back in and it wont start. The engine is getting fuel and spark. the exhaust is getting warm but just wont fire.

Here is the list of new parts.
plugs
plug wires
cap n rotor
Header
fuel pump and filter
crank position sensor
harmonic balancer
cam shaft

Please help with anything else to try.
Thanks in advance.

87manche
August 26th, 2011, 11:25
timing

assuming you had the distributor out, double check it.

kdub41
August 26th, 2011, 11:34
probably not it but check the neutral safety switch.I have a 96 cherokee and mine wouldnt start except for in neutral then it wouldnt start at all :( took out the safety switch and it was all gummed up. I had my buddy help me with it but i know how to do it now.

RyanKnol
August 26th, 2011, 12:28
are the injectors firing? I had that issue once where after cleaning the injectors and putting them back in, i messed up the order of the wires, and it wouldnt start.

But I dont think youd be getting spark or anything if this were the case.

ehall
August 26th, 2011, 12:56
probably not it but check the neutral safety switch
it wouldn't turn over with a bad NSS

ehall
August 26th, 2011, 12:59
We got the engine back in and it wont start. The engine is getting fuel and spark. the exhaust is getting warm but just wont fire.
Hold the throttle down while you crank and see if it catches, this will bypass the IAC.

How are you testing fuel to the cylinders?

supertubesocks
August 26th, 2011, 14:00
I've checked the fuel using the relief valve on the rail, and also used a stethascope on the injectors, they are all clicking.
We suspect timing is the issue, but it seems like the rotor is pointing at plug#1. Is there any other components in the ignition system to check?
The engine cranks and tries to fire but just wont run.

kdub41
August 26th, 2011, 14:14
whooops i didnt see that is was turning over.

nblanton
August 26th, 2011, 17:00
Do you have spark?

supertubesocks
August 26th, 2011, 17:14
Do you have spark?

Yes, we pulled the wires and put an old plug on them.

Originally we were only getting one spark but then i replaced the cps and it's getting good spark.

Could it have anything to do with the wiring harness hooked up incorrectly?
There were 3 wires with ring terminals on the left side of the engine bay that i just grounded to the engine block.

Is there an ignition control module that i can check?

djgrayxj
August 27th, 2011, 06:38
Note from DJ
You might take a look at this posting
Renix distributor install walkthrough
http://www.naxja.org/forum/showthread.php?t=964617 (http://www.naxja.org/forum/showthread.php?t=964617)

supertubesocks
August 27th, 2011, 10:00
Note from DJ
You might take a look at this posting
Renix distributor install walkthrough
http://www.naxja.org/forum/showthread.php?t=964617 (http://www.naxja.org/forum/showthread.php?t=964617)

Does that apply to HO distributors?