Changed my plugs and now runs rough
11-25-2010, 03:20 PM
#1
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Model: Cherokee
Changed my plugs and now runs rough
Hi guys i been reading and i see this symptom alot.runs rough,hot soak,misfire#3 all that stuff.Mine started after a plug change.Fine when its cold,warms up,sudden loss of power,chuggs rough.
Why would a plug change do this? the plugs that were in there were clean but you could tell they were in there awhile(larger gap slightly)
This thing does have 180K miles on it! 2000 XJ 4.0
It does not have the "wrap" fix on #3 injector-was fine before plug change.
It does have a slight sound like a diesel,is this a lifter problem maybe?
Why would a plug change do this? the plugs that were in there were clean but you could tell they were in there awhile(larger gap slightly)
This thing does have 180K miles on it! 2000 XJ 4.0
It does not have the "wrap" fix on #3 injector-was fine before plug change.
It does have a slight sound like a diesel,is this a lifter problem maybe?
11-25-2010, 03:50 PM
#2
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Year: 1996
Model: Cherokee
Engine: 4.0
sounds like the a plug is dirty, happened to me before, good cold but once warmed up it bogged around,
so i would repull the plugs starting with 3 and look for dirt, or if the end is pushed down?
good luck, hope i helped
so i would repull the plugs starting with 3 and look for dirt, or if the end is pushed down?
good luck, hope i helped
11-25-2010, 03:53 PM
#4
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Year: 1999
Model: Cherokee
Engine: 2.5L MPI (Throttle Body Spacer, Intake)
Are you sure you put the plug wires on the right plugs. Yours sounds like they might be mixed up.
11-25-2010, 03:55 PM
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Year: 1992
Model: Cherokee
Engine: 4.0
You have to ask yourself what changed before you messed with it?
1. The plugs. Are you running a different brand. Is the gap correct? Did you crack an insulator installing them?
Jeeps run best when you use Champion plugs!!!
2. The wires. Are they in good shape? Did you separate one of the connectors from the wire while removing them? Is the insulation cracked?
Use dielectric in the boots to eliminate moisture and make good contact to the plug.
Find a dark location, open the hood and run the engine and see if you see any arching.
PLEASE DO NOT DO THIS IN A CLOSED GARAGE!!! I want you and your family to have a good holiday season.
1. The plugs. Are you running a different brand. Is the gap correct? Did you crack an insulator installing them?
Jeeps run best when you use Champion plugs!!!
2. The wires. Are they in good shape? Did you separate one of the connectors from the wire while removing them? Is the insulation cracked?
Use dielectric in the boots to eliminate moisture and make good contact to the plug.
Find a dark location, open the hood and run the engine and see if you see any arching.
PLEASE DO NOT DO THIS IN A CLOSED GARAGE!!! I want you and your family to have a good holiday season.
11-25-2010, 04:13 PM
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Year: 1994 1993
Model: Cherokee
Engine: 4.0
I'd pull the plugs again and look them over as one might be misfiring for some reason. (I'll assume you changed one at a time and didnt cross any wires.) I've messed up a few times in my life changing plugs and cracked one or bent a tip changing the gap or scrapped the wall caking the plug with grease thus shorting it. Anythings possible so I'd look them over again.
11-25-2010, 04:17 PM
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Year: 1994 1993
Model: Cherokee
Engine: 4.0
Good advice! This is how I accidently found the problem last time I messed up a spark plug change. Changed the plugs and went for a ride and it was running badly and I couldnt figure out why. Pulled into a parking lot and since it was dark out (It was night time) a flicker of light caught my eye and looking closer I saw the one plug hole had a spark going from the side of the plug to the block because I had cracked an insulator.
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11-25-2010, 04:54 PM
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It has the coil packs on it,cant mess that up lol I will pull the plugs back out and look for cracks and condition. also will look in the dark for arcing-thanks!
11-25-2010, 04:58 PM
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Year: 1992
Model: Cherokee
Engine: 4.0
Even being a 2000 and has the coil packs it still has a boot and contact/spring between the coil and plug and the same rules apply!
Dielectric grease in those boots is a really good idea.
Dielectric grease in those boots is a really good idea.
11-25-2010, 05:05 PM
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you know i was wondering when i pushed them back on if it was connecting good or not...its funny how it comes and goes...the check engine light comes on when it runs rough too.
11-25-2010, 05:13 PM
#11
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Year: 1992
Model: Cherokee
Engine: 4.0
Yup. Just recheck it and you will most likely be ok. The check engine light is the system getting ready to throw a misfire code. Really pay attention to the way the coils seat on those plugs.
Keep us posted.
Keep us posted.
11-26-2010, 12:09 AM
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Well i checked the plugs,all is good with them.when its cold it runs great,turn it off a few min and get in and the engine light is on and it feels like its stumbling.
I have to give it alot of gas to get it going then floor it and it takes off...but let off at about 45 with enuf gas to maintain speed and it feels like the rear end kinda jumps.WTH Then the engine light is flashing then stops after 10 seconds remains on...wow all i did is change the spark plugs and oil...i looked down in the spark plug boots on the coil pack and they are alike and look great.What did i do??? help
I have to give it alot of gas to get it going then floor it and it takes off...but let off at about 45 with enuf gas to maintain speed and it feels like the rear end kinda jumps.WTH Then the engine light is flashing then stops after 10 seconds remains on...wow all i did is change the spark plugs and oil...i looked down in the spark plug boots on the coil pack and they are alike and look great.What did i do??? help
11-26-2010, 02:58 AM
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Dude, take advice. Firing order is 1-5-3-6-2-4. Remember it by this; 15 is too young, 36 is too old, and 24 is just right. lol.
Check that you're wires are running to the right cylinders, and if they are, pull each plug one by one, and visually inspect them.
Check that you're wires are running to the right cylinders, and if they are, pull each plug one by one, and visually inspect them.
