Replacing spark plugs
#31
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
Were you sure to correct the gap to .035?
How did the coil pack come off? Did it bend or anything? I can almost bet that one of the boots didn't seat all the way when you put the pack back on.
How did the coil pack come off? Did it bend or anything? I can almost bet that one of the boots didn't seat all the way when you put the pack back on.
#32
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Joined: Feb 2012
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
There should be 3 lugs on the coil. Loosen the screws to the coil and push on and wiggle the pack while pushing on each lug. There is 1 lug per 2 plugs I think.
Then tighten it back down.
Is it missing at idle? Can you give it gas and smooth it out?
Did you leave the lock washer on the new ones?
Then tighten it back down.
Is it missing at idle? Can you give it gas and smooth it out?
Did you leave the lock washer on the new ones?
Last edited by Crazy Amos; 07-10-2012 at 08:03 PM.
#33
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From: Central Arkansas
Year: 1996
Model: Cherokee
Engine: 4.0L
Changing plugs shouldn't make anything worse. Ever. Unless... 1) wrong plugs 2) incorrect installation, ie wrong gap, wrong firing order, damaged or cross threaded plug, damaged or improperly seated coil pack
#34
Thread Starter
Senior Member
Joined: Dec 2011
Posts: 690
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Okay okay let me re-phrase this. I did the spark plugs correctly. Every boot was seated. I triple checked. It still isn't any better. The shaking happens occasionally, the check engine light goes on and blinks, and the shaking occurs, usually just after I start the Jeep. Gunna go to autozone and get some more codes tested. Either way it was time for a spark plug change. I could see that just by looking at the old ones.
For the coil, anything I should try to adjust/twist/move around to help it work better? I think I might just need a new one. I even used the dielectric grease and all. Didn't help.
I did the right gap, antiseized the threads, hand twisted in til tight, made sure the coil's boots or whatever fit snug over each spark plug. Should I check the coil's wiring? What should I look for?
For the coil, anything I should try to adjust/twist/move around to help it work better? I think I might just need a new one. I even used the dielectric grease and all. Didn't help.
I did the right gap, antiseized the threads, hand twisted in til tight, made sure the coil's boots or whatever fit snug over each spark plug. Should I check the coil's wiring? What should I look for?
#35
Thread Starter
Senior Member
Joined: Dec 2011
Posts: 690
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Originally Posted by Crazy Amos
There should be 3 lugs on the coil. Loosen the screws to the coil and push on and wiggle the pack while pushing on each lug. There is 1 lug per 2 plugs I think.
Then tighten it back down.
Is it missing at idle? Can you give it gas and smooth it out?
Did you leave the lock washer on the new ones?
Then tighten it back down.
Is it missing at idle? Can you give it gas and smooth it out?
Did you leave the lock washer on the new ones?
It misses at idle sometimes, but less now I feel like. Mostly yes to the gas.
Yes to the washer.
#36
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
That is a "Multiple Misfire" not sure of the technical code term for it but that is what it is.
When it spits and sputters on start up like that and the CEL blinks, typically that is what happened.
The next few times you start it, allow the chime to ring 4 times and hold the key in the start position longer than usual or until the starter ka spinning freely and see if it happens after starting it like that for a few starts.
You may have a faulty injector and/or a leak in the fuel system.
You haven't noticed your coolant levels going down or milky oil or anything have you?
When it spits and sputters on start up like that and the CEL blinks, typically that is what happened.
The next few times you start it, allow the chime to ring 4 times and hold the key in the start position longer than usual or until the starter ka spinning freely and see if it happens after starting it like that for a few starts.
You may have a faulty injector and/or a leak in the fuel system.
You haven't noticed your coolant levels going down or milky oil or anything have you?
Last edited by Crazy Amos; 07-10-2012 at 11:21 PM.
#37
Thread Starter
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Joined: Dec 2011
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Originally Posted by Crazy Amos
That is a "Multiple Misfire" not sure of the technical code term for it but that is what it is.
When it spits and sputters on start up like that and the CEL blinks, typically that is what happened.
The next few times you start it, allow the chime to ring 4 times and hold the key in the start position longer than usual and see if it happens after starting it like that for a few starts.
When it spits and sputters on start up like that and the CEL blinks, typically that is what happened.
The next few times you start it, allow the chime to ring 4 times and hold the key in the start position longer than usual and see if it happens after starting it like that for a few starts.
#39
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Joined: Feb 2012
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
Maybe when you were pulling the coil pack off, the wiring harness pulled out a little.
There may be a ground wire for the pack that got loosened. Seems like I read somewhere it had one, or it said to be sure NOT to knock a specific ground wire loose. Maybe someone can correct me or be more specific about it.
There may be a ground wire for the pack that got loosened. Seems like I read somewhere it had one, or it said to be sure NOT to knock a specific ground wire loose. Maybe someone can correct me or be more specific about it.
#40
Thread Starter
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Joined: Dec 2011
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Originally Posted by Crazy Amos
When you put the plugs in, did any of them scrape the sides to where any gunk would have stuck to the electrode?
#41
Thread Starter
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Joined: Dec 2011
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Originally Posted by Crazy Amos
Maybe when you were pulling the coil pack off, the wiring harness pulled out a little.
There may be a ground wire for the pack that got loosened. Seems like I read somewhere it had one, or it said to be sure NOT to knock a specific ground wire loose. Maybe someone can correct me or be more specific about it.
There may be a ground wire for the pack that got loosened. Seems like I read somewhere it had one, or it said to be sure NOT to knock a specific ground wire loose. Maybe someone can correct me or be more specific about it.
#42
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Joined: Feb 2012
Posts: 312
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From: Kentucky
Year: 2000
Model: Cherokee
Engine: 4.0
Originally Posted by luckyAD80
Can you explain the first part of your post more? I'll try that.
It misses at idle sometimes, but less now I feel like. Mostly yes to the gas.
Yes to the washer.
Try loosening the coil pack, just back the screws out 3 or 4 threads just enough the allow you "level" the pack across the plugs.
Once loosened, grab the middle "lug" or raised part that is molded into the coil pack and wiggle it up and down, in the direction of the hood, then the ground while pushing in the direction of the plug axis to try and get the two middle plugs to seat. Then do the front lug the same way and then the rear,
Then snug the two middle screws, then the two outer. Then tighten them down, but tighten the opposite ones as before. Meaning if you snugged the outer front screw first, then tighten the outer back and then the front.
While you are there, check to see if the wiring harness in the back of the pack is tight in the connector. It is on the back of the pack.
Last edited by Crazy Amos; 07-10-2012 at 11:38 PM.
#44
Thread Starter
Senior Member
Joined: Dec 2011
Posts: 690
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
Alright I think I'm going to replace the coil. Friend at autozone thinks that the heat must if f'd up the electronics. Should solve my problems. Codes now indicated that 1,2,3 and 4 were misfiring. It has to be the coil, what elae could it be?
#45
Thread Starter
Senior Member
Joined: Dec 2011
Posts: 690
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From: VA
Year: 2001
Model: Cherokee
Engine: 6 cyl
OKAY, I am spacing out or something, but I distinctly remember learning the correct ft-lbs to torque the bolts on the coil covering the spark plugs to, but I can't remember/find it now. Anybody know? Thanks and sorry for reviving this thread.