green50gt
10-02-2009, 07:55 PM
Ok this is driving me absolutely nuts. Jeep is running poorly. Pulled the injector plugs off cylinders 3 and 5 and absolutely no change in idle. I had those 2 injectors checked at the local machine shop and they were fine. I pulled back everything on the injector harness from the injectors back to about the brake booster looking for cuts or breaks, and all looks fine. On the other side, the plugs/wires/cap and rotor have all been replaced. Here's the kicker, this weekend the Jeep ran perfect for about a day and a half. This is what made me think wiring?
What is going to be more likely, something wrong with the distributor, or the harness/computer? I suppose the next easiest thing to do is pull the plugs on 3 and 5 and see if there is spark.
Has anyone seen or heard of this before? I would super appreciate any help you can give. Thanks.
Fyathyrio
10-03-2009, 10:44 AM
No check engine light?
Pull the plugs, compare to this chart, (http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm) and let us know what you find.
Could also be bad plug wires, bad or dirty distributor...what else have you done besides check injector wires?
green50gt
10-04-2009, 10:34 AM
1 maybe 2 of the old ones looked overheated, the rest all looked normal. Replaced all plugs all wires cap and rotor...Before I figured out 3 and 5 misfire I changed the TPS, and IAC valve. No just sitting there running it will not throw a code. The cat was shot so it was replaced with strait pipe with 02 provisions a new muffler was installed. The head gasket was replaced by the previous owner, the head was sent in and checked and found good. (had previous overheating issues. I think thats about it.
PA-XJ2
10-04-2009, 12:37 PM
I had the same problem with one of my XJs, i also replaced TPS, IAC, MAP, plugs/wires/cap&rotor, it turned out to be the injectors them self need to replaced. www.fiveomotorsport.com they have good prices
PA-XJ2
green50gt
10-04-2009, 06:22 PM
Ok, thank you for the input. I sent the injectors into Napa and they tested ok, but they went ahead and cleaned them anyway. I am at a loss. Next step is check the injector plugs for a signal, then pull the plugs and look for spark?
JonTJ
10-05-2009, 07:44 AM
Why not just swap the questionable injectors to different cylinders and start pulling injector wires again. Then you'll be able to isolate if it's the injectors themselves that have bit the dust.