How often do truck coils go bad?
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From: PNW
How often do truck coils go bad? Noticed this a couple weeks ago, was never like this before. Car ran fine, just assumed age was the culprit. Well this weekend at the track the car seemed to be slowly going down on power until you could distinctly hear it dropping a cylinder. Now anything over half throttle it’s very much dropping a cylinder.
Pulled the plugs and they all look fine - I think it may be this coil and those insulation cracks are from overheating from an internal short drawing way too much current. I have a line on some of those Accel supercoils I could go grab right now, but if this is more of a fluke than anything, I’ll pass on that and just get another truck coil.
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Probably not a bad coil but who knows.
The wiring doesn't look like overheating to me; looks like it chafed against something somehow at some point. Mechanical damage.
I'd change out that pigtail FOR SURE. That's obviously fornicated. There's no "maybe" or "probably" or "I wonder" about that. See what that does for it first.
The wiring doesn't look like overheating to me; looks like it chafed against something somehow at some point. Mechanical damage.
I'd change out that pigtail FOR SURE. That's obviously fornicated. There's no "maybe" or "probably" or "I wonder" about that. See what that does for it first.
Noticed this a couple weeks ago, was never like this before. Car ran fine, just assumed age was the culprit. Well this weekend at the track the car seemed to be slowly going down on power until you could distinctly hear it dropping a cylinder. Now anything over half throttle it’s very much dropping a cylinder.
Pulled the plugs and they all look fine - I think it may be this coil and those insulation cracks are from overheating from an internal short drawing way too much current. I have a line on some of those Accel supercoils I could go grab right now, but if this is more of a fluke than anything, I’ll pass on that and just get another truck coil.
Given that copper wire is exposed, in the coil pack harness I would replace that first. It rubbed against something at some point. Might have issues else where. Just to save potential head aches, I'd check the other side carefully as well.
Also discovered the hard way, after an LS swap sometimes the four pin connectors in the older / used coil pack harness plug that goes into the coil pack sometimes don't make a good connection. I tweaked the end of the connector with a small Philips to get it to connect better on one coil pack harness plug. That fixed it for a few weeks. One can also replace the end connector if that's an issue or replace the while coil pack harness. I ended up replacing the coil pack harness. They get brittle from the heat and vibration. Took about a year and a half and 5,000 miles for the old used coil pack harness to go bad.
FWIW - There are some low quality copycat truck coil packs out there. Unknowingly, had set set on my 91 RS that cause a similar issue in 6th gear. Four of eight ended up proving defective. Ended up with a new set of Denso coil packs and tossed the copycat junk in the trash. The coil packs failed quickly like in less than 200 miles.
Good luck, it can be an annoying issue.
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From: PNW
These are original OEM coils. Original OEM harness. Replacing the harness is obvious, but there was nothing rubbing it. Not only is there nothing near it - but doesn’t it seem odd that whatever you think was rubbing it somehow magically went over and around the other two wires without leaving so much as a mark? It’s because this isn’t a rubbing issue.
Back to my original question;
Should I get a replacement one of these or just get a set of Accel Supercoils?
Back to my original question;
Should I get a replacement one of these or just get a set of Accel Supercoils?
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That wire and harness cover and all that has been RUBBED. That damage isn't from heat.
I can see that there's nothing rubbing on it NOW; but something, at some point in the past, DEFINITELY has been. Might have been while you were doing some other work to the truck or something, hard to say what; but that's mechanical chafing, pure and simple.
If it had been heat, the copper wouldn't be all nice and shiny, like it's been scraped; and the wrap wouldn't be all frizzy like that. And, the connector would be melted. It's safe at this point to rule out heat.
"The simplest explanation that fits all the facts is most likely to be the right one". Heat doesn't follow that simple truism.
I think you should fix the wire now and see if it clears up what ails the car, and leave the coil question for later.
I can see that there's nothing rubbing on it NOW; but something, at some point in the past, DEFINITELY has been. Might have been while you were doing some other work to the truck or something, hard to say what; but that's mechanical chafing, pure and simple.
If it had been heat, the copper wouldn't be all nice and shiny, like it's been scraped; and the wrap wouldn't be all frizzy like that. And, the connector would be melted. It's safe at this point to rule out heat.
"The simplest explanation that fits all the facts is most likely to be the right one". Heat doesn't follow that simple truism.
I think you should fix the wire now and see if it clears up what ails the car, and leave the coil question for later.
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That wire and harness cover and all that has been RUBBED. That damage isn't from heat.
I can see that there's nothing rubbing on it NOW; but something, at some point in the past, DEFINITELY has been. Might have been while you were doing some other work to the truck or something, hard to say what; but that's mechanical chafing, pure and simple.
If it had been heat, the copper wouldn't be all nice and shiny, like it's been scraped; and the wrap wouldn't be all frizzy like that. And, the connector would be melted. It's safe at this point to rule out heat.
"The simplest explanation that fits all the facts is most likely to be the right one". Heat doesn't follow that simple truism.
I think you should fix the wire now and see if it clears up what ails the car, and leave the coil question for later.
I can see that there's nothing rubbing on it NOW; but something, at some point in the past, DEFINITELY has been. Might have been while you were doing some other work to the truck or something, hard to say what; but that's mechanical chafing, pure and simple.
If it had been heat, the copper wouldn't be all nice and shiny, like it's been scraped; and the wrap wouldn't be all frizzy like that. And, the connector would be melted. It's safe at this point to rule out heat.
"The simplest explanation that fits all the facts is most likely to be the right one". Heat doesn't follow that simple truism.
I think you should fix the wire now and see if it clears up what ails the car, and leave the coil question for later.
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From: PNW
Jesus f’n Christ. Heat dries up plastics, makes them shrink and become brittle. THAT is the simplest answer why only one single wire would be affected while all the others are completely fine. You should take your own advice.
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From: Central Cal.
You know, YOU came here looking for help. You put up a pic of the problem; some very knowledgeable guys looked at it and offered the most logical solution to the apparent issue. But you are such a freakin' knowitall that you blow them off. Typical for you. You post on other threads ridiculing others with your superior attitude, but most of us have caught onto your crap. And here you are with a problem. You know it all, YOU FIX IT, then jump in a hole and die. You've burned this bridge.
You know, YOU came here looking for help. You put up a pic of the problem; some very knowledgeable guys looked at it and offered the most logical solution to the apparent issue. But you are such a freakin' knowitall that you blow them off. Typical for you. You post on other threads ridiculing others with your superior attitude, but most of us have caught onto your crap. And here you are with a problem. You know it all, YOU FIX IT, then jump in a hole and die. You've burned this bridge.
Well said These are original OEM coils. Original OEM harness. Replacing the harness is obvious, but there was nothing rubbing it. Not only is there nothing near it - but doesn’t it seem odd that whatever you think was rubbing it somehow magically went over and around the other two wires without leaving so much as a mark? It’s because this isn’t a rubbing issue.
Back to my original question;
Should I get a replacement one of these or just get a set of Accel Supercoils?
Back to my original question;
Should I get a replacement one of these or just get a set of Accel Supercoils?
I've soldered/burnt wires and that pic doesn't look like the insulation has signs of heat especially on just one particular wire while the rest look and coloring are fine. it actually looks like something clawed at it, squirrel maybe? I had it happen once on my lifted jeep. ripped my coolant temp wire apart.
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I think, since you're logic-proof, that you should now find the most expensive kind of coil there is, and waste your money on that. Of course you'll then complain that it's crap and a rip-off because it didn't fix the problem but that's OK too.
I guess there are people in the world that you just can't help.
I guess there are people in the world that you just can't help.
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From: Central Cal.
I think, since you're logic-proof, that you should now find the most expensive kind of coil there is, and waste your money on that. Of course you'll then complain that it's crap and a rip-off because it didn't fix the problem but that's OK too.
I guess there are people in the world that you just can't help.
I guess there are people in the world that you just can't help.
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From: South Florida
Try & keep this short. I also agree with G Atsma.
To your problem. That wire was physically chaffed. Or eaten lol. Have seen little guys get their eat on wires. About the coil as the culprit? Well, hopefully you know what cylinder is dropping. Swap that coil for another & see if the miss follows the coil. Then you may know. Oh and coils don't go bad much on these engines as they run at 1/8 of what a normal ignition coil would. Doesn't mean they can't go bad.
To your problem. That wire was physically chaffed. Or eaten lol. Have seen little guys get their eat on wires. About the coil as the culprit? Well, hopefully you know what cylinder is dropping. Swap that coil for another & see if the miss follows the coil. Then you may know. Oh and coils don't go bad much on these engines as they run at 1/8 of what a normal ignition coil would. Doesn't mean they can't go bad.
Confession
He rubbed his teeth on your delicious electrical wires and will probably do it again
King Talon, You definitely need to order some new coils from Maryland Speed or 6LE Designs. In fact, two set would be best so you can have back ups.
You know, YOU came here looking for help. You put up a pic of the problem; some very knowledgeable guys looked at it and offered the most logical solution to the apparent issue. But you are such a freakin' knowitall that you blow them off. Typical for you. You post on other threads ridiculing others with your superior attitude, but most of us have caught onto your crap. And here you are with a problem. You know it all, YOU FIX IT, then jump in a hole and die. You've burned this bridge.
Last edited by 99 Black Bird T/A; Sep 18, 2018 at 09:33 PM.
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From: PNW
I stopped monitoring this thread because of everyone's obsession with chafing. But a little update:
No change after replacing the sub-harness and the coil. I narrowed the problem cylinder down to #2 and after rechecking the plug, I see that it is a bit sootier than the others. I clearly over-looked it because I was so focused on the #1 coil. Threw the new coil on that one instead - still no change. Tomorrow I'll try swapping the sub-harness on that side and see if anything happens but I doubt it. I've not treated this engine very well (accidentally, not purposely) it may just be tired and in need of freshening up.
No change after replacing the sub-harness and the coil. I narrowed the problem cylinder down to #2 and after rechecking the plug, I see that it is a bit sootier than the others. I clearly over-looked it because I was so focused on the #1 coil. Threw the new coil on that one instead - still no change. Tomorrow I'll try swapping the sub-harness on that side and see if anything happens but I doubt it. I've not treated this engine very well (accidentally, not purposely) it may just be tired and in need of freshening up.