moonfriedpotatoes

Hey folks, new to this forum since i don't own a jeep. My girlfriend does however (it's a 2000 V6 w. 125000 miles on it), and we just figured out that the 3rd cylinder is misfiring.

What do you all suggest I do to stop this? the mechanic who pulled the codes for me told me i should change the spark plugs, which i know how to do. anything else I should do/look for before/after I change the plugs? Any other reason the 3rd cyl could be misfiring? what else does a tune up consist of?

thanks so much,

chris

mike albo

also try replaceing the plug wires that could be couseing the miss fire to

MrJCRod

There is a TSB out there for cyl 3 injector vapor locking after shutting off engine and then trying to restart after a short time... Dealer should have it on there computer. They should have insulated #3 injector to correct it... Mine does the same thing. I still didn't insulate the injector, I'm going to actually cut the hood and put hood vents in which should let all the heat out and hopefully solve my problem... if you do a search on here I'm sure you will find it.

pulled this from an automotive forum:

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).

jbarkalow

I have a 2001 Jeep Cherokee with the 4.0 engine.

I have placed the insulator around the number three injector as described in the bulletin but it still happens after a 20 minute heat soak.

I would greatly appreciate any information on how to correct this issue.

Thank you!