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Coil on plug connector issues

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Well, after many months of pulling my hair out, we found the problem causing intermittent misfires and poor running. The connectors from the wiring harness to the coil packs.... apparently, the quality of the connection between the plug on the harness and the pins on the coil, degrades after some time. This car is a 100% track car, and has seen almost 20K track miles. Still has the OE harness. When the car begins to run poorly, we've been able to repeat the fix at the track a few times: Remove each COP connector from the coil pack, carefully bend all of the silver tabs (2 per connector, using a pic) to make better contact with the pins on the coils, carefully replace each connector.

These are really fussy, little delicate things. All I can assume is that heat/cold cycles and track duty begin to fatigue these things. Next purchase is a new OE harness....I guess. I can't find anyone that knows of an upgrade for this. If you do .... Please Post!!

BTW - months ago when this all started, I had Mustang "gurus" tell me that my motor was toast. It's not, we checked everything, including doing a leak down test and all is great. That, and combined with the fact that when the connectors do their job correctly, the car runs like champ.

Anyone else have this issue??
 
Sounds like you need the upgraded wiring harness and connectors. I believe @ArizonaBOSS and @Black Boss might have some info to share on that subject. BTW glad you finally got this "pinned" down.
 
@tetstang The 2012 had issues with the harness for the Cam sensors/actuators and the Crank position sensor. Fix for that was either the '13 harness (or more robust) an upgrade from PRS who did the 302S upgrades.

Not aware of coil pack connection issues on the Boss, but 20k track miles is a lot and 8k more than I did in the Boss!
 
Damn...that's a sweet car #58. Do you have contact info for PRS ? BTW - I talked to Watson Engineering yesterday on this and they said they did not know of any upgrades and to replace the harness (with OE), and the cycle will likely repeat. Talked to someone at Kenny Brown as well with same reply.
 
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Thanks !! My car is a 2012 (build date of 10/11/11) GT, not a Boss. You mentioned using the '13 model year harness. Ford Parts nor the dealer parts guy can tell me if the later harness will work on my car. My part # off my existing harness matches a usage date of 8/16/10 thru 12/8/11. The later usage dates in 12/8/11 forward to 6/27/14. Can I use the later one?

Any help here will be greatly appreciated! If the later usage date harness is compatible with my car, maybe the issue will be resolved (although not at the level of the PRS stuff, agreed).
 

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