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Posted

 

     I am at my wits end with this 8 coil pack no start ******. My truck has been down for 8 months now. I changed Transmissions and at first  there was no spark no start and finally realized with all of your guy’s help it was the crankshaft position sensor plug wires. Fixed that put a new Nuetral Safety switch in with new wires. Well in the process here I blew my pump in my tranny pulled the tranny for the fourth time and put in a new pump. I put in new plug wires, spark plugs are new a few months back, they  look good, I have checked all the fuses and relay’s, all the grounds, checked for pinched, broken or bare wires, changed camshaft position sensor, checked battery cables, checked the ECM it’s good, brand new fuel pump, checked the security system, It had spark and started before the last pulling of the Tranny. I have not checked the ignition switch or anything in the cab other then the fuses, I can’t imagine it being all 8 coil packs they looked good. So I just can’t seem to figure out what I havemissed, (almost ready to call a mobile mechanic)…. Hopefully someone out there can give me something for my check list I have gotten on there yet. I have watched thousands of You Tube videos, checked, double , triple checked things I just don’t know….please somebody HELP! lol….

 

Posted

If you're not seeing spark at the plugs I would be checking the coil pack harness, make sure they are both plugged in tight, then check the harness grounds. Make sure the one on the back of the cylinder head is bolted in place.

Posted (edited)

And make sure a male pin didn't get bent over inside that plug for the coil harness. 

 

Something to try (I may have mentioned this on your other thread) - on the driver's side plug for the coil harness, the bottom row of wires (hardest to see, naturally ...), I believe it's a black wire and the last one all the way closest to the firewall / cab (DOUBLE CHECK THIS FIRST so you don't fry anything - I'm going off of my memory, which can be dangerous these days ...) - ground that wire and see if you have spark.

 

If you do, then just splice a wire into that one, run it up to the firewall to that long stud sticking out about in the center of the cab, crimp an eyelet connector on the end of the wire, remove the nut on that long stud, install the eyelet, and tighten the nut back down. You now have an alternative ground, rather than fishing around behind the power steering pump. The ground there is a common failure point and causes a no-spark condition.

Edited by Jsdirt
  • Haha 1
Posted (edited)

Yes you have told me that in the past, thank you I thought it might be a ground I will do that and let you know how it turns out. I appreciate you answering I almost hope you answer me I kinda have come to rely on you answering. Thank you.

  What about the other coil harness plug on the passenger side? Does that one ever need to be checked? 

Edited by Liz Kozel-Gill
  • Like 1
Posted

No, would be the wire underneath - last one on the right of the bottom row of wires. I can't tell the orientation of the picture, but I don't remember the wire being pink. DO NOT ground that until you're sure of what wire is what.

 

That does look like the plug - if it's sitting on top of the driver's side valve cover, then that's it. Just double check with a Alldata DIY subscription, or a printout of  a wiring diagram to be sure you'll be grounding a GROUND wire, and not anything else.

  • Like 1
Posted

Do your other plugs/harness connections look like that? That does not look at all like a factory connection/parts used.

Posted (edited)

This is what the 4 coil packs and the plug look like. Drivers side.IMG_1963.thumb.jpeg.7eeb3ba6fe24fadcb0691117a316eb4c.jpeg

Edited by Liz Kozel-Gill
Posted

Yep, that's it. 

 

Going off memory, I believe I tapped into the lower half of that plug, bottom row (hardest to see), all the way to the right (closest to cab / firewall). Was a black wire if I remember right. Probably easier to tap into the top wire, no doubt.

 

Just to check ... get an INCANDESCENT (NOT LED) test light, connect the clip to battery POSITIVE, unplug that connector and touch it to that wire (make sure the key is OFF) connector in the lower half of that plug (don't jam the pointy end in there - just TOUCH it lightly to make electrical contact). If the test light lights up, turn the key ON and test it again. If it is still lit up, then that is the correct ground wire.

Posted

Okay  I must be retarded or something. I guess I have just been at my truck fixing thing too long! This photo shows the white plug I was suppose to find the ground wire on the bottom row of wires add a longer ground to it and run it to the neg side of the battery right? Well for some reason I went to the coil pack to the left of that white plug, and see the plug on top of the coil pack? I added a ground wire to that ground and ran it to the battery? I am not sure what I was thinking but I don’t even have the right plug more or less the right ground wire. Did I just mess things up worse by doing the coil pack plug instead of the white plug? I am my own worst enemy! IMG_1963.thumb.jpeg.d2e65c3e64ced51c118a9c32d5438468.jpeg

Posted
On 4/15/2024 at 10:40 AM, Jsdirt said:

Yep, that's it. 

 

Going off memory, I believe I tapped into the lower half of that plug, bottom row (hardest to see), all the way to the right (closest to cab / firewall). Was a black wire if I remember right. Probably easier to tap into the top wire, no doubt.

 

Just to check ... get an INCANDESCENT (NOT LED) test light, connect the clip to battery POSITIVE, unplug that connector and touch it to that wire (make sure the key is OFF) connector in the lower half of that plug (don't jam the pointy end in there - just TOUCH it lightly to make electrical contact). If the test light lights up, turn the key ON and test it again. If it is still lit up, then that is the correct ground wire.

Well as you can see from my latest photo I don’t have a black wire on the white plug at all! lol … for now I will try and find out which one of the wires there is my ground and do what you said.

Posted

Yeah, don't do that - you'll fry the coil to a cinder.

 

Best money you can spend is on a AllData DIY wiring diagram. Trust me on that one! It's cheaper than replacing fried components.

 

Like I said, I'm not 100% sure what the wire color is there since I'm going off memory ... which is fickle on my best day.

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