Nick1234

I have a1996 xj all it will do is spit and sputter and pop back through intake like timing is off. I bought jeep with this problem. Has rebuilt engine.. new parts I've installed cps, throttle position sensor, new disturber plugs wires and rotor. New computer fuel pump and I've checked all injectors and jus about everything I can think of.. tried to time the engine every way possible I know I've pulled the distrubter about 50 times to make sure it was right or to move it one tooth out.. please any help will be greatly appreciated, thanks

cruiser54

http://www.angelfire.com/my/fan/dist_index.html

Nick1234

thank you but I have done that already and all I can get is missing and sputtering at best. I've also moved it a tooth forward and backwards just to see if any changes and it will not even try to start.. I'm starting to think that when they built the engine that they may have the timing chain a tooth off. I really have no clue but I have tried just about everything I know to do

CCKen

The timing chain may be off from rebuild but that's usually unlikely.

You may want to try these steps to see if the distributor has been installed properly.

1, outline the timing mark on the crank vibration damper using grease pencil, paint stick, etc. so can be easily seen. Get at it from under the engine.

2, remove the radiator electric fan so you can get an unobstructed view of the timing mark on the damper and the timing index marks on the timing chain cover.

3, mark the side of the distributor body just below the #1 plug wire post on cap.

4, remove the distributor cap, rotor, and camshaft position sensor, then reinstall the rotor.

5, rotate the damper clockwise until the damper timing mark aligns with the zero (0) timing mark on the timing chain cover. If you go past the zero mark, back up the damper 90 degrees and slowly bump the damper up to the zero mark again.

6, at this point the rotor should be pointing just past the #1 plug wire mark you placed on the side of the distributor body. If pointing at #6, turn the damper 360 degrees to realign the timing marks.

7, at this point you should be able to insert a 5/16" pin punch or drill bit down through the plastic ring in the distributor and down through the alignment hole in the distributor body. If it doesn't drop through, the distributor is not installed properly and must be reinstalled with the pin punch in place.

At this point, if there is a doubt as to whether the timing chain has been installed correctly, remove the valve cover and see if both #1 cylinder rockers can be freely moved/rocked. If there's any tension it may mean the valve is being opened and the chain has been installed improperly. This is not the dead nuts procedure for checking the chain. The FSM has you using a dial indicator for this.

See pics.

Pin punch installed in the 4.0 alignment hole (reference):



.
Pic shows the position of the rotor when the pin punch is installed and the damper timing mark is aligned at zero (0). You can also see a dot painted on the distributor body below the #1 plug wire post. I installed this modified cap as reference.



.
Timing marks:



.

Nick1234

Ok I've done the distributer with a punch and can not get it to line up dead nuts with the bolt hole that hold disturber in place I've tried it every way possible but it's a little off I have to pull punch and move it just a little to line up.. I have not pulled the valve cover off but will do that maybe tomorrow if I have time. Thank you very much

CCKen

I understand what you are saying about the distributor hold down fork aligning with the hold down clamp bolt hole (as seen in my pic above).

FYI: Be aware that the 4.0 L and the 2.5 L distributors look alike. The only difference is that the 2.5 distributor drive gear helical splines are not aligned on the distributor shaft the same as the 4.0. If the rebuild people and you installed a 2.5 distributor it may never be installed properly.

This pic shows the 4.0 L distributor drive gear helical spline alignment and the pin punch protruding through the alignment hole (index hole) in the boy of the distributor.



.

Nick1234

Yeah I was lining it up in the disturber body was not using punch to line bolt down hole up.. and I was saying once it was in place the fork would not line up correctly with the bolt hole I have to turn it just a little bit to line up I've tried every way possible and only was it lined up perfect was if I had it 180 out of time.. I did not know that about the distrubter difference in the 2. I have a buddy with another distrubter I will try.. thank you very much

CCKen

When you pull the distributor out check to see if the spline lines up like in the pic I posted.

CCKen

You did verify that #1 cylinder at TDC compression when the damper timing mark is lined up didn't you?

Nick1234

Yeah it's at Tdc on compression stroke. Jus got another disturber and tried that and it was the same way I will post a pic of how it lines up in just a min

Nick1234

Nick1234

Ok so I had a friend put a good snap on computer on it today showed no codes at all. He cleared all memory out of computer and it cranked up and ran fair at about 1/4 throttle but was still missing some and running rich but it also acted like it was trying to start running better. I am going to put new injectors in tomorrow because it had very old bad gas in it. I cleansed tank and flushed lines out prior to doing all the other work I have on it.. I have a video of it running but do not know how to upload it on here

CCKen

deleted

Nick1234

..

Nick1234

Just wanted to let everyone know I found the problem. The roll pin on the cam shaft sprocket was sheered causing it to be out of time