Rough Idle and CEL after tune up -
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Unread 06-24-2010, 10:42 AM   #1
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Join Date: May 2010
Location: Newfoundland
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Rough Idle and CEL after tune up

Hey everyone

So last week I decided to do a tune up on my 97 TJ (6 cylinder). Spark Plugs i removed were old but in fairly good shape.

I replaced the air filter, the plugs and wires. Used Champion double platinum plugs and champion wires. Since the tune up the TJ has been idling rough and the CEL has come on. When idling it sounds like it is misfiring and it smells of unburnt gas. Also exhaust from tail pipe, while not smoky, is a little black.

I rechecked all the plugs and wire and the plug has a nice black coating on them (after only 200km or so) and the mileage has noticeably declined.

Any idea what may be the problem? The jeep was fine before i did the tune up so not sure why is is acting up now!

deacfire is offline   Reply With Quote
Unread 06-24-2010, 10:49 AM   #2
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2004 TJ Wrangler 
Join Date: Feb 2008
Location: Indianapolis
Posts: 19,307
Don't use double platinum plugs in the older motors. Switch to the standard plugs and you'll be good to go.
Float Test Build
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Unread 06-24-2010, 12:49 PM   #3
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2005 LJ Wrangler 
Join Date: Feb 2010
Location: Louisville, KY
Posts: 787
Change the plugs. Use plain old stock plugs.
2005 Unlimited Rubicon, too much junk to list!
My build: [url][/url]
Unlimitedlou is offline   Reply With Quote

rough idle , cel , check engine light
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