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Changed plugs+wires, jeep idles very rough and major loss of power

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Old Jun 23, 2012 | 09:55 PM
  #1  
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Angry Changed plugs+wires, jeep idles very rough and major loss of power

Hey guys, I'm new to the forum and I just picked up my first Jeep yesterday for $700. I got the old plugs out and they were terrible. I put the new wires in and went to start it up and man this thing sounds terrible. I triple checked the wire order. When I was wrenching on it earlier my extention bridged the battery terminals and it shorted out. It still had power. Would that have something to do with it? I reset the battery and drove it a little bit to see if the computer would return to normal. Im not sure what the problem is.
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Old Jun 23, 2012 | 11:41 PM
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If something goes to heck after I make changes, I undo the changes one by one until the problem goes away. New plugs, wires, etc aren't always good.
I'd pull the plugs and check them over, perhaps re-install the old ones temporarily. Swap the old wires back one by one, See what happens. That may not be it, but you'll at least rule it out.
Shorting the battery momentarily shouldn't hurt anything. Other than an arc mark on your wrench.

Last edited by Radi; Jun 23, 2012 at 11:43 PM.
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Old Jun 24, 2012 | 12:25 AM
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Yea, Agreed^, with the addition, my dad, (the OSHA inspector), found that shorting it with a metal watch band can cause a nasty burn.

87-90 Renix jeeps defiantly wouldn't have a problem...your year and trans should be in your post. You should always check the new plugs....035. 153624 (clockwise), from 5:00, viewed from the side. A bunch of the diagrams in the books are wrong. #1 is here, on the yellow thing..
Attached Thumbnails Changed plugs+wires, jeep idles very rough and major loss of power-jeep-1-location.jpg  

Last edited by DFlintstone; Jun 24, 2012 at 01:14 PM.
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Old Jun 24, 2012 | 12:55 AM
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Sounds like the firing order isn't right
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Old Jun 24, 2012 | 01:56 AM
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Originally Posted by pickles
Sounds like the firing order isn't right
x2

and or one of the wires isn't seated and you have a non firing cylinder. and or a plug that was dropped hard on concrete that isn't firing
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Old Jun 24, 2012 | 04:34 AM
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What kind of plugs did you put in? And did you verify you had the gap correct?

Firing order is definitely suspect here too, as said above.
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Old Jun 24, 2012 | 08:20 AM
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[QUOTE=DFlintstone;1854778]Yea, Agreed^, with the addition, my dad, (the OSHA inspector), found that shorting it with a metal watch band can cause a nasty burn.

Wedding ring shorted between solenoid and ground on a 24 volt military truck. Bad burn and vaporized half way through the ring.

I'm gonna jump on the firing order bandwagon just because I've seen it so many times.
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Old Jun 24, 2012 | 08:30 AM
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I agree with pretty much everything above, another thought, if the plugs and wires were in that bad of shape, did you check the cap and rotor as well??
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Old Jun 24, 2012 | 10:37 AM
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Thanks for all the input guys. The plugs and wires were in rough shape and I'm surprised it actually ran. I did review the firing order in my Haynes manual and double checked that each wire clicked on the plug. Today I will just change the new back to the old one by one to see if I got a bad wire or something. The plugs I got were NGK and the wires are BWD from O'Reillys.
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Old Jun 24, 2012 | 10:41 AM
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Start the Jeep and pull one wire off at a time. Each time you remove a wire take note if the engine ran the same or worse than it had been running. If it runs worse with that wire removed then that wire is not the problem. You're looking for a wire that doesn't make a difference in the way that it runs.

Don't get shocked.


Also, are you sure it's the right rotor button? Is it seated properly?
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Old Jun 24, 2012 | 10:45 AM
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I believe it is the correct rotor button. I never changed anything down there and it ran fine before. I seated the boots on the plugs firmly until they clicked like they are supposed to.
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Old Jun 24, 2012 | 11:58 AM
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Return the ngk's.

Install whats recommended by Jeep. I run champions in my 01.

Ive seen COUNTLESS people install incorrect spark plugs and cause a misfire situation.
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Old Jun 24, 2012 | 12:19 PM
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Originally Posted by the buddmang
Return the ngk's.

Install whats recommended by Jeep. I run champions in my 01.

Ive seen COUNTLESS people install incorrect spark plugs and cause a misfire situation.
Your 2001 came from the factory with NGKs.....

NGK coppers will work very well if the gap is right and the firing order is correct.

From 87-99, they came with Champion coppers
From 00-01, NGK coppers
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Old Jun 24, 2012 | 12:20 PM
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The firing order has to be off...

Verify:

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Old Jun 24, 2012 | 12:35 PM
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I put on the original plug wires and it still runs like crap. I have NGK plugs in it. My next step will be to get some champions and see if the plugs were the culprit. Thanks for all the input guys.
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