Running rough
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Running rough
Decided to change the plugs and wires on my 86 because they were quite old. Now that this has been done, it's running rough as hell. Any gas acceleration causes backfires. It was running smooth prior to the plug/wire change. 
Le Mans Master
Joined: Mar 2004
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From: Ft. Lauderdale Fl
My first guess would be a crossed wire. Double check the order.
Safety Car
Joined: Jun 2006
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From: FL
See if this link helps. Another possibility is a cracked plug, easy to do when changing them.
http://autorepair.about.com/library/...s/bl256lib.htm
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I was careful to replace one wire at a time. I just double checked and they all appear in order. Hmmm.
I'm thinking of disconnecting (one at a time) every spark plug wire as the engine is running to see if there is a drop every time. Any other ideas?
I'm thinking of disconnecting (one at a time) every spark plug wire as the engine is running to see if there is a drop every time. Any other ideas?
Last edited by charv66; Apr 14, 2010 at 03:19 PM.
Safety Car
Joined: Jun 2006
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From: FL
That should work, but it may be easier to remove the wires at the cap. Once you find the weak one check the plug for cracks or a closed up gap.
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She's running smooth and strong.
-Vince
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From: Winnipeg Manitoba, Canada
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Running Rough
Mry '90 ran real rough after installing new plugs. Turned out, the gap was nearly closed on one plug when they were installed. Based on what you described, it either has to be one bad plug, or one wire isn't "clicked" onto the plug properly.
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