Hello everyone,

First time poster definitely a long time reader. Like the title says I've been having troubles with my 2012 5.7 Charger. Issues started last week. I was on my way home and my car started running rough. CEL popped on so I made my way to the parts store. They ran the code and said it was either my coil packs or my spark plugs on cylinder 2. Went home and replaced the "faulty" pack. Pulled the plugs from cylinder 2,4, and 6. Compared each other and seemed to be consistent (replaced them last year and have put about 10k miles on). Switched cylinder 2 plugs with cylinder 4 plugs. Continued to run rough.

Fast forward to the next day. Took the injectors out and cleaned them. Threw some Sea Foam in the tank as well as Lucas Oil to clean the lifters. Tested the wire harness for both the coil pack and the injectors. Injector came back pumping .03 volts. Meanwhile the coil pack harness wasn't pushing anything.

Fast forward again to late this week. Grabbed a few new wire harnesses for the coil pack. Replaced them and tested it electricly. When we would connect the positive to the positive on the wire harness and then grounded it to the frame of the car we would get 14 volts. However if we would plug the harness in and ground it to the car the plugs wouldn't fire. It has been throwing the Ignition Coil Secondary circuit code as well. My best guess is that the car wants to complete a circuit with the computer and not just anything which is why it won't spark. I don't really feel like digging into my computer and making my workload even bigger.
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​At the moment I'm at a loss. I can't think of anything else. I'm considering selling it to get it off my hands but I love this car. Thank you everyone for possible suggestions. If anyone has questions please let me know.
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PCM controls ground side for both coils, and injectors. It completes the circuit for a few milliseconds to fire the injector, it BREAKS the circuit momentarily to fire the coil. Test resistance across the injectors, they should all be within an ohm or two of each other, and I *think* they are suppose to be around 12 ohms. Too much, or too little, and things don't work the way they are supposed to.

 

Thank you! If it turns out to be a PCM issue could it just need to be cleaned since it just happened to one cylinder or do I need to buy a completely new PCM?

 

PCM's don't really fail all that often in this manner. I would test both the coil connector, and injector connector with noid lights, to see if the PCM actually IS doing it's job there. You can rent them at your local auto parts store....