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Won't Start after Changing wires HELP

3195 Views 16 Replies 5 Participants Last post by  KyleZ71
I put on a set of pro form valve covers today, and since the coils get moved away, I had to get longer wires (MSD) for they are mounted on top. After getting everything mounted and plugged in, the truck will not fire. It turns over but simply will not fire. To me it seems like the wires are too taught, and that could be preventing the spark. I also thought that the coil packs are out of order but I thought the packs themselves don't have a order. What do you guys think?
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I know the harnesses are connected but not the ends... now I'm gonna plug a wire in to each wire and see if they spark
if the connectors are not getting down into the coil holes then you will not have spark. Well, you might have spark, it just will not travel thru your wires. Most the time you hear a significant click noise when you push the wires into the coil. You might melt a standard wire if you plug it into the plug wire. I do not suggest doing that. I would pull a spark plug out, plug it into a wire and set it against the engine block and crank it to check for spark.
Got spark, got fuel (can smell) but still no start. Everything is hooked up, and grounded. :neutral:

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Guess ill bite the bullet, again, and take it to the garage.
Yes, I have one bolt fastening them to the bracket that sits on the top side of the valve cover. Didn't think this would be so frustrating
Ok it has been one week since the truck was picked up and taken to a local repair shop. The mechanic said that the wires were not long enough and the accel wires were not the correct ones. SO after ordering a custom set of MSD LS wires, the mechanic said the truck STILL will not start. He said when hooking it up to his computer it reads misfire but won't say where. He said it could be too much fuel in the engine, bad coils, or bad ECM. So frustrated right now because I do not want to try to lets replace and see what works game. Do you guys think it would better to get it towed to the GM dealer as they're computers are better and mechanics are better trained?? Please help
Thanks for the response Pikey. I know for a fact the knock sensor were hooked up because that was my project only days before. The packs did have two bolts holding them on but the remount kit would only allow me to use one bolt. Maybe that's the problem. When changing the valve covers and gasket I read that it is not uncommon for oil to get on the plugs themselves. I did not pull the plugs, only putting a spare on each wire itself to ensure a spark. Hoping just oilly plugs. I too agree that all 8 packs shouldnt go bad at once and the same with the computer.
To my knowledge no there wasn't any insulation, just metal on metal, but then again I haven't been under the hood of my truck in a week.

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Well another day goes by without the truck. Hate that I have to call each day to find out the status
Almost after two weeks I am now leaving to get the truck back. Here something in the wiring harness to the packs got messed up. Just glad to be able to drive it again. Hope I don't pass out when I see price
dying to find out what was wrong.... and see the price tag lol
He said the coil pack sub harness was messed up and needed to be replaced. Price tag was 633.99, that was after complaining about the time it took. That was two thirds the price he would've charged. Said it took 7 hours. Needless to say the garage took advantage of me, royally.
Oooh that sucks!!! But look at it this way, at least he found it and got it running. The Chevy dealer would have charged at least $1,000 if not more, fancy tools don't make a better mechanic IMO.
I don't know, I was thinking it would've been cheaper. The day before he finished the job I called Apple Chevrolet up to check about them taking on the project and they said that the wiring harness was most likely the problem and would be the first thing they replace.
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