Ignition Problem after plug gapping

[WorkinLonghorn]

Truck was running nearly perfect but gas mileage was a little low and power seemed off and it has been 40-50K miles since I looked at the plugs (standard plugs, not platinum).
I'm running a Skip White Distrib. and have had no problems in years.

Ok, so I broke a plug while tightening it due to carelessness. I needed to move the truck to get my car out so I could drive to the parts store. I usually ground a free plug wire before I start the engine but I wasn't thinking too well today and started it up with the one wire hanging loose unattached. I just ran for about 1 1/2 minute to move the truck out of the way.

After installing the new plug and finishing the re-gap job (they were all at ~.055", now .045) I fired it up and there was a dead cylinder. I pulled the wire from the new plug and the idle seemed to stay the same. I pulled and grounded the plug and noticed a weak orange spark instead of a crisp blue one. I then put a different new plug in there and same result. The truck idles very poorly and there may be another dead cylinder, not sure because sun was down and I quit for dinner.

My question is; Can running for a minute and a half under 1500 RPM with one plug wire off cause damage to the electronics in a High Energy Ignition system?

Or maybe I cracked some other plugs?

Or some wires started to come apart at the ends?

I'm pretty bummed, I have to miss a day of work tomorrow during my crazy busy season. Thanks- WL

Oh, I only disconnected one plug at a time so there is no chance of incorrect routing.

[badherb]

I have zero experience with High Energy Ignition system. However it is possible you ground faulted the plug wire. This I'm sure could cause issues. But before I freaked out I would pull each plug and make sure each one was still good no cracks and and nothing broken then I would look at the ignition system. I'm guessing that the stronger sparking system could jump out of the boot to metal but its a long shot and not a likely culprit. check each end of the offending cylinders plug wire and insure each end has a tight connection. nothing new here but you never know maybe you lost yer head after it ran like crap. good luck

[special-K]

I suspect the plug wire is the issue if nothing has changed. If you fried anything in the ignition I would think it would affect all cylinders.

[turbotruck]

plug wire

[turbotruck]

Originally Posted by WorkinLonghorn

Ok, so I broke a plug while tightening it due to carelessness. I needed to move the truck to get my car out so I could drive to the parts store. I usually ground a free plug wire before I start the engine but I wasn't thinking too well today and started it up with the one wire hanging loose unattached.

what do you mean by this?

[snj8198]

isolate that wire to determine if it is the problem. just switch it with another wire and see if you get the same results from the wire in question in the new location.

[Wrenchbender Ret]

Check inside the dist cap. You probably have a carbon track between 2 terms.

[Ironangel]

Originally Posted by special-K

I suspect the plug wire is the issue if nothing has changed. If you fried anything in the ignition I would think it would affect all cylinders.

"What he said!"

[WorkinLonghorn]

Originally Posted by turbotruck

plug wire

BINGO. Wire had touched the manifold and was brittle and cracked when I moved it I guess.

I went ahead and replaced all the wires, cap, rotor and coil just to future-proof it a bit ($93 total) I can't have any more down time.

Thanks for all the suggestions.

Turbotruck asked what I meant about shorting out an unattached wire; I always heard (and this might just pertain to points type original ignition) that if you ran the engine with some wires not in place on the plugs, then you needed to ground those wires with a nail or some other means to some ground or it would burn the points or something, or damage the coil? can't remember- but I'm sure I read that in multiple locations eons ago. -WL

[mike16]

I would look at the wires, I never seem to be able to remove plug wires without tearing them up. Does not seem to matter weather they are 19 dollar cheapo set or the million dollar MSD/Accel sets.


sometimes they separate internlly and you cant see the separation.

I cant believe that technology has not evolved enough that.... for the asking price of some wire sets.... we cant make a set that does not self destruct while being serviced.

Nobody puts up with that BS in the aviation industry.

[WorkinLonghorn]

Well Mike, the AC Delco wires that I bought 10 years ago (?) were quite sturdy and thick (8mm size). Compared to the other brands I just shopped they really are nice, but not designed to touch exhaust manifolds!
There is an AC Delco wholesale place near here but they wanted $55 for wires so I settled for the best ones "Pep Boys" had. I'm back in business.

[RichardJ]

use a dielectric such as the one below and it makes the next plug wire removal a much easier job.