vague question...
11-12-2011, 03:12 PM
#1
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Year: 2001
Model: Cherokee
Engine: 4.0l I6
vague question...
My CEL is on n has been on for about 2 weeks. Anyways, had the codes read and said cylinder 3 misfire and something about cat emissions dot dot dot...
So off the top of anyones head, what can i do to fix it? Its a 01 4.0 sport.
Any help is appreciated and apologize in advance for the lack of info
So off the top of anyones head, what can i do to fix it? Its a 01 4.0 sport.
Any help is appreciated and apologize in advance for the lack of info
11-12-2011, 03:59 PM
#2
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Year: 2000
Model: Cherokee
Engine: 4.0 I6 H.O.
My sensor on my #3 spark plug is the only thing ever to set off a code. This happens to my Jeep if I drive it all day for long distances. The reason for this is the number 3 piston gets too hot after awhile and the only solution Ive heard is to sleeve the piston or put in a coil pack. I havent done either I just try not to drive it too far
11-12-2011, 04:27 PM
#4
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Year: 2001
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Engine: 4.0l I6
Not that i can see. Coolant looks fine. Im a stickler for fluids n all that cuz i dont want my header to crack which my model is known for.
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11-12-2011, 06:26 PM
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Year: 2000
Model: Cherokee
Engine: 4.0 L
misfire and cat
Slim possibility but . . . check the connection at the injector.
My CEL on. I had a rough idle, cylinder 4 misfire and cat issues when I pulled codes. (My 2000 has the 3991 head)
I had just replaced the spark plugs, so I pulled the coil pack and checked the gaps. Seemed OK. Put some dielectric grease on the plugs and reinstalled. No improvement.
I then thought about a "lean" misfire situation. I checked the plug at the injector. A bit loose. pushed the plug lock and slide the plug on and off the injector a bit to clean the connection. slid it back on completely and snug.
Started up. misfire fixed. Cleared codes and job was done.
My CEL on. I had a rough idle, cylinder 4 misfire and cat issues when I pulled codes. (My 2000 has the 3991 head)
I had just replaced the spark plugs, so I pulled the coil pack and checked the gaps. Seemed OK. Put some dielectric grease on the plugs and reinstalled. No improvement.
I then thought about a "lean" misfire situation. I checked the plug at the injector. A bit loose. pushed the plug lock and slide the plug on and off the injector a bit to clean the connection. slid it back on completely and snug.
Started up. misfire fixed. Cleared codes and job was done.
11-12-2011, 06:38 PM
#11
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Year: 2000.1999,1996
Model: Cherokee
Engine: 4.0
My sensor on my #3 spark plug is the only thing ever to set off a code. This happens to my Jeep if I drive it all day for long distances. The reason for this is the number 3 piston gets too hot after awhile and the only solution Ive heard is to sleeve the piston or put in a coil pack. I havent done either I just try not to drive it too far
--------Also does it do this after you restart the motor when it is still hot?Need more info.
11-12-2011, 08:39 PM
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Year: 2001
Model: Cherokee
How's the idle after a hot restart?.....Could be a heat soak problem....00's and 01's seem to be more apt to have this issue....
This is the TSB from Jeep.
TSB
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.
This is the TSB from Jeep.
TSB
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.