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coils not firing need help

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Old Sep 16, 2012 | 09:10 PM
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Default coils not firing need help

so ive racked my brain with this for months now still no answer

some of the coil will not fire but all coils are working

there is no breaks in the wire's . crank sensor has been replaced an no codes are binging thrown

i really need to get this car running im trying to move from florida to new york very soon and cant afford to leave it behind
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Old Sep 17, 2012 | 08:16 AM
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did you try switching the coils around to see if the non-firing one still doesnt fire, or if you have a dead spot in the wiring? it may be a corroded harness (the harness that connects all 4 coils to the main harness). do you know which particular ones do not fire? is it the same ones failing every time?
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Old Sep 17, 2012 | 08:24 AM
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yes it is the same 1 every time, and they work when i switch them around the dead spots are constant 1,2,3,6 are not firing, idk if my volt meter not working right but i think it is, im getting signal from i can tell to all the wires
getting anywhere from .2 -.5 depending on location
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Old Sep 21, 2012 | 11:13 AM
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bump.... any 1
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Old Sep 21, 2012 | 11:24 AM
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You have a wiring problem forsure. Just keep diggin
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Old Sep 22, 2012 | 06:30 AM
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Are the wires on the correct coils?
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Old Oct 8, 2012 | 12:55 PM
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ive checked threw all the wires there no breaks no sign of rats or anything everything looks good and the coils can only be plugged in the right way
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Old Oct 8, 2012 | 03:11 PM
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So you checked the wiring from the coils all the way back, and did you try swapping the spark plug cable on that coil with another one ?
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Old Nov 5, 2012 | 08:41 PM
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ive checked the wires no breaks, its getting signal all the way to the coil, and if i switch the coil's location they work, all test has been done pre spark plug wire, so that is not a factor
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Old Nov 5, 2012 | 09:01 PM
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Do we have cam sensors on these?? Stupid question, but I completely forgot.

I'd say check the grounds too. Check the electrical section for the ground thread, or search for it.
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Old Nov 8, 2012 | 08:50 AM
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its not throwing a code for the cam sensor. and i know the 3 grounds on the back of the head are good, perhaps i need to trace them down to where ever they go and check out the other end
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Old Nov 8, 2012 | 11:32 AM
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Look at the pin cavities on both of the coil pack harnesses. The connectors that plug into each coil pack and the female end of the connector where the coil pack harness plugs into the engine harness.

Check the silver electrical female terminals inside the cavities in the connectors and look to see if any of them looked to be stretched opened. If they are use a pick to pull down on the little "tab" of the terminal to ensure there is a good contact between both the female and male terminals.

The silver terminal in this picture you want to make sure is not stretched from having unplugged and plugged in the connector a bunch of times.

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Old Nov 9, 2012 | 01:56 AM
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o i never even thought to check that. yeah this would make sense because if i put a volt meter probe in there i get a signal, but when i plug it in to the coil its not firing. thank u for the advice im going to try this tomorrow, an see what happens
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Old Nov 9, 2012 | 07:58 AM
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Yeah if you have been jamming a volt meter probe in there chances are there is a big gap in the terminal and its not contacting the male end when you plug them in. Good luck!
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Old Nov 10, 2012 | 12:50 PM
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I am having the same issue on my 03 Silverado. Except, none of my coils fire and they all have good grounds and signals. I've swapped them out and still nothing. I changed the cam and crank sensors, no codes are being thrown either. If you some how figure it out let me know, I'm going to keep digging and if I figure it out I'll shed some light on it for you as well.
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Old Nov 10, 2012 | 12:58 PM
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injector fuse or terminal, try wiggling them.
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Old Nov 10, 2012 | 02:00 PM
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Do you know what the inj fuse would be labeled? I checked all of the ign and ecm/pcm fuses.
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Old May 27, 2020 | 11:37 AM
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Same issue im having # 1 7 4 6 coils not firing although my reluctor wheel hasn't been removed I have power to the coils just not getting signal from the pcm need help please
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Old May 27, 2020 | 12:19 PM
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Here you are tagging onto an EIGHT year old thread. START A NEW ONE.
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