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Solved Odd missfire 2003 4.0

Post number 3 has been selected as best answered.

Nctruckman

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1994 Explorer XLT 4-Dr
I changed out the plugs and wires on my 03 4.0 ST Saturday, motorcraft plugs, autozone wires.
We had a storm and it blew blooms all over it. I was rinsing off the hood with a garden hose, when I noticed the hood wasn't latched all the way down. Nothing seemed wet.
I've noticed now it'll missfire/ backfire under anything more than half throttle. No codes.
I tried replacing the maf thinking it was that, to no avail. If I drive/ accelerate easy, it won't missfire hardly at all. Coil pack is oe ford within the last 6 months. Before these missfires, it ran perfectly.

Any thoughts on this?
 






Rick

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Check your wiring again to ensure all the plug wires are routed correctly. You could also check the resistance of the plug wires to see if perhaps you got a bad one in the new set.
 






Nctruckman

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1994 Explorer XLT 4-Dr
Check your wiring again to ensure all the plug wires are routed correctly. You could also check the resistance of the plug wires to see if perhaps you got a bad one in the new set.
Issue was some bad plug wires. Apparently they were internally damaged when I changed plugs
 






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