my jeep headache

[Hudson]

yeah, well least i have time to tinker with it now cause i dont have to use it every damn day lol thanks gents

Even more time now that the geo is out of commission.

[92xjlaredo]

Even more time now that the geo is out of commission.

oh no Geo is good to go got two new bolts and prevented the other side from doing the same thing. haha

[StompJrKz400]

I guess we NEED to find that o2 harness finally

[StompJrKz400]

The rear 02 sensor does nothing besides monitor catalytic converter function. The rear 02(the one you're trying to fool to keep the check engine light off) does not at all effect air fuel or engine performance, EVER. For that matter you could yank the cat, unplug the rear 02 and drive it with the check engine light on and you're still not going to see a performance decrease.

From an 8 year certified jeep mechanic ( speaking about a tj 4.0 )

[StompJrKz400]

Ian, ever see this bulletin?

I think this is may be it.....
1803103 - 4.0L ROUGH ENGINE IDLE AFTER RESTART FOLLOWING A HOT SOAK
Date: 09/05/03 (supercedes 1802702 dated 09/06/02)
Model Year(s): 1999-2004

Description: NOTE: This bulletin applies to vehicles equipped with a 4.0L engine. This bulletin involves the installation of a fuel injector insulator sleeve.

Details: Customers may describe a 20 to 30 second rough idle following the restart of a heat soaked engine. This condition may be most noticeable when the engine is restarted following a prior 10 to 20 minute heat soak in hot ambient conditions of approximately 32 C (90ºF) or higher. This condition may be consistent with short city stop-and-go driving trips and can be aggravated by the use of fuel with a high ethanol content. Depending upon various conditions a MIL may occur due to DTC P0303 - Cylinder #3 Misfire.

This condition may be caused by heat from the exhaust manifold that following engine shut down migrates to the area around injector #3 and causes fuel vapor to form within the injector. This in turn may cause a momentary misfire of cylinder #3 until the fuel vapor is cleared of injector #3. The insulator sleeve lowers the injector #3 temperature to a point below which the fuel will not normally vaporize.

If vehicle exhibits a rough idle, and if a misfire of cylinder #3 is observed following a 10 to 20 minute hot soak, perform the Repair Procedure.

Parts required:
56028371AA Ignition Wire Shield

Repair procedure:
1. Cut insulator sleeve, p/n 56028371AA, to make two (2) insulator sleeves about 25-30 mm (1 in.) in length. See diagram.
2. Install one sleeve around injector #3, with the slit on the upward facing side of the injector. Install the other sleeve with the slit on the downward facing side of the injector.
3. Confirm sleeve is flush to intake manifold surface around injector.
4. Check injector #3 wire and ensure that the injector is rotated to a 2 o'clock position (from driver?s side of vehicle).
to a the letter...

[92xjlaredo]

The rear 02 sensor does nothing besides monitor catalytic converter function. The rear 02(the one you're trying to fool to keep the check engine light off) does not at all effect air fuel or engine performance, EVER. For that matter you could yank the cat, unplug the rear 02 and drive it with the check engine light on and you're still not going to see a performance decrease.

From an 8 year certified jeep mechanic ( speaking about a tj 4.0 )

I have heard this many a time, and the CEL doesn't bother me ever, like I said previously, the jeeps been that way since I bought it...and you remember, there was a time that thing ran fantastically.

[92xjlaredo]

Hmmm, I suppose when I get around to it ill have to look at that, haven't seen that article yet

[StompJrKz400]

yeah well i dont know how typical heat soak is in a 96, but i know you have different injectors, i wonder if maybe you have a bad injector, which would make it more susceptible to heat soak, what injectors do you have again?

if wouldn't be a bad idea to get a spark no fouler ( for 3.99) from auto zone, and throw a 02 in there, but there is no point in putting a cat in,

i also read on fuel check valve, making it run bad for the first few minutes, but it doesn't sound like thats it, either way we should hook up my meter to your rail

[StompJrKz400]

find the impedance of your injectors, we will test them cold then hot and see if one if fucked

[92xjlaredo]

Compression across all six was good, 1-6 respectively.

130, 150, 130, 140, 150, and 130 rougly. Haynes manual says they should be from 120-150 with no more deviation than 30 psi

[justtorchit]

yeah well i dont know how typical heat soak is in a 96, but i know you have different injectors, i wonder if maybe you have a bad injector, which would make it more susceptible to heat soak, what injectors do you have again?

if wouldn't be a bad idea to get a spark no fouler ( for 3.99) from auto zone, and throw a 02 in there, but there is no point in putting a cat in,

i also read on fuel check valve, making it run bad for the first few minutes, but it doesn't sound like thats it, either way we should hook up my meter to your rail

I understand your point of not putting a cat in there..... Yeh it's not gonna change a thing but ya might as well weld a new one in with the bung for an o2 sensor.

I knooooooow for a fact that that fucker can make shit run bad. Kappy had one that had torn wires an would arc out and shut his jeep off. Made it run like shit all the time..... What If the non existent harness is just snipped and grounding out.? I'm not saying its a problem but they put an o2 sensor in for a reason. Might as well fix it.

Ad once your lite goes out for the o2 maybe it will pop on with another o2 code. Therefore meaning your upstream o2 is bad. And that will without a doubt make it run like shit.

[StompJrKz400]

I understand your point of not putting a cat in there..... Yeh it's not gonna change a thing but ya might as well weld a new one in with the bung for an o2 sensor.

I knooooooow for a fact that that fucker can make shit run bad. Kappy had one that had torn wires an would arc out and shut his jeep off. Made it run like shit all the time..... What If the non existent harness is just snipped and grounding out.? I'm not saying its a problem but they put an o2 sensor in for a reason. Might as well fix it.

Ad once your lite goes out for the o2 maybe it will pop on with another o2 code. Therefore meaning your upstream o2 is bad. And that will without a doubt make it run like shit.

i hear you, its just when he bought the jeep with all that removed already, it ran great. but yeah, we need to find the wires, shouldnt be that hard, unless the PO cut them right outa the main harness for some dumbass reason ( which wouldn't surprise me )

[92xjlaredo]

i hear you, its just when he bought the jeep with all that removed already, it ran great. but yeah, we need to find the wires, shouldnt be that hard, unless the PO cut them right outa the main harness for some dumbass reason ( which wouldn't surprise me )

funny enough while checking compression on #6 today after breaking the plug off and replacing it....i found what i think is the o2 sensor plug....couldnt pull it out and into the engine bay though ... not without crawlin around in the muck

[92xjlaredo]

put a fresh battery in it. cranked over really hard....ended up reading 12v flat no key just battery, then while cranking 10.2v..and while running 13.8v still made no difference in the running of the POS