Strange Ignition Coil Question

Hello--this one is a bit odd, hoping someone might have some insights. Last December I had my plugs, wires, and coils changed out on my '95 Riv 3800 SC, after a misfire under load was detected that was causing lurching and jumping at times when going up hill under light throttle (but the check engine light was never triggered). The tune-up cleared it up and she was running like a charm until about a week ago, when I started getting the up-hill lurching issue again (but much less frequently than before). Figured there might have already been a failure somewhere among the new wires or coils. But just yesterday when I went underhood and looked at the coils, I noticed dead bug body parts wedged between the coil-side boot of one of the ignition wires and a post of one of the coil pairs. So I popped that boot off the coil and cleared the bug parts out. Since I did that, the car seems to start much more briskly, and the engine seems to run a lot smoother and the trans seems nice and crisp in its shifts, and no sign thus far of the intermittent uphill lurching. So my question to the hivemind is: could dead bug parts be enough to divert some of the coil's current and cause intermittent misfires? Has anyone every heard of anything like this? Or is this just wishful thinking on my part? Right now I'm taking a "watchful waiting" approach over the next couple of days to see if there's any sign of the misfires returning.

My guess is the new wire boot in question wasn't seated all the way on, or otherwise wasn't making good connection. Popping the boot off and on fixed the issue (bug parts or not).

haywardwilliamc@gmail.com wrote:

Hello--this one is a bit odd, hoping someone might have some insights. Last December I had my plugs, wires, and coils changed out on my '95 Riv 3800 SC, after a misfire under load was detected that was causing lurching and jumping at times when going up hill under light throttle (but the check engine light was never triggered). The tune-up cleared it up and she was running like a charm until about a week ago, when I started getting the up-hill lurching issue again (but much less frequently than before). Figured there might have already been a failure somewhere among the new wires or coils. But just yesterday when I went underhood and looked at the coils, I noticed dead bug body parts wedged between the coil-side boot of one of the ignition wires and a post of one of the coil pairs. So I popped that boot off the coil and cleared the bug parts out. Since I did that, the car seems to start much more briskly, and the engine seems to run a lot smoother and the trans seems nice and crisp in its shifts, and no sign thus far of the intermittent uphill lurching. So my question to the hivemind is: could dead bug parts be enough to divert some of the coil's current and cause intermittent misfires? Has anyone every heard of anything like this? Or is this just wishful thinking on my part? Right now I'm taking a "watchful waiting" approach over the next couple of days to see if there's any sign of the misfires returning.

Was the bug burned?

Anything that can prohibit full contact should be considered an option.

Most recently I have detected that the top of my coil boots do not seal tightly. Moisture gets in and fouls the contacts resulting in misfire. I'm hoping dielectric grease top and bottom helps with seal.

IFallsRon wrote:

Anything that can prohibit full contact should be considered an option.

Most recently I have detected that the top of my coil boots do not seal tightly. Moisture gets in and fouls the contacts resulting in misfire. I'm hoping dielectric grease top and bottom helps with seal.

It will help temporarily but you might want to $ for new boots (if you have Taylor, MSD, Magnecor or other high-spec wires) or new wires. Depends on your $ of indifference and what quality you want. I did a quick check -- Boots, sleeves, pliers and crimpers are available on eBay - prices are all over the place - and Rock Auto is having a 'wholesaler closeout' on wires, they are not giving them away but it's close at less than $10.-/set. Not surprisingly the ACDelco wires are at regular price. United premium wires (apparently the same Delphi Packard wire as OE) are not on closeout but less then $20/set.

Point is, maybe just replace the wires.

Which reminds me, I need to get my Magnecors repaired. Some time ago they started acting up and I put on a new set of OE wires in the interim.