Possibly Stupid - Definitely Long - Coil Question: C'mon! I Dare You!

[snaxforgandhi]

'94 Ranger XLT Lariat Supercab, 3.0 V6 OHV, 4-speed A4LD



OK, I know I'm gonna hear all about how stupid this question is, but I gotta ask. First, however, because I'm a guy I feel I must qualify that I am a tool & die machinist and have been building engines and racing various internal combustion engine powered vehicles since I was wee high, so I'm not a total moron. (Just don't ask my wife)

So, here's the question: Is there any legitimate reason why one should be able to visually discern (overly-technical term for "see") any faint arcing - or possible plasma glow - on/near/around the ignition coil and coil wire in very low-light or completely dark conditions? Now, obviously one's coil shouldn't be arcing and sparking all over the place, and I wouldn't even ask except that I have never really had much occasion to spend a lot of time gazing under the hood in complete darkness and what I saw was fairly low energy (but definitely there), so I don't know if what I'm seeing is abnormal or simply a normal manifestation of high energy/high-ratio transformers (like automotive ignition coils).

Here's the haps: Just after the first big snowstorm of the winter (Huge dump in the pacific northwest, you may have seen the aftermath on network news during the past week or so) I noticed an occasional but pronounced "stutter" while cruising at 55-60mph. As it was pre-dawn, freezing cold and on snow and ice packed roads I quite frankly couldn't really decide whether it was a not-quite-up-to-temp engine, the tranny slipping in 3rd (its a tired old A4LD) or if I was simply losing traction in spurts. I had just recently tracked an EGR gripe to a bad DPFE (since replaced) that had given the engine over to stuttering fits upon acceleration so I immediately pulled over and pulled the vacuum line from the EGR valve itself and plugged it. No joy. Pulled over again and checked the ATF for capacity and condition: full and unburnt. Pulled over again, this time under a huge pine bough overhanging the shoulder where it was quite dark, and before I got my flashlight turned on I happened to noticed this faint blue glow around the coil and down along the right/rear bank. Upon closer inspection I saw that there appeared to be either a faint but definitely visible and near-constant arcing, or possible glowing plasma (flux leakage?), going on in the very narrow space between the plastic encased "coil" portion of my ignition coil and the "wings" of it's laminated core. I also noticed the same thing going on along the coil wire anyplace that it ran closer than about 0.125" to anything metallic; ATF dipstick tube, plug wire bracket, etc. I grabbed my telescoping inspection mirror to try to see up under the coil "wings" and noticed that I could induce the same plasma-lookin' arc between the steel mirror frame and the coil if I got close enough. Same thing when I placed mirror frame near coil wire.

This tells me, based upon what I know of BE&E, that the coil's laminated core, ATF dipstick tube, plug wire brackets and my inspection mirror's frame all possess a difference in potential great enough to induce the arc. Right? Also, I know that high ratio transformers (which ignition coils are) tend to run to the inefficient side of things and are prone to flux leakage. Right? So am I just seeing a normal small static charge generated by the EM flux off the large secondary shunting to chassis ground? Or is my coil and/or wire freakin' out?

Any help would appreciated. Thanx.

[alchymist]

Wow, you sure know a lot of big words......anyway, what you do in that situation is spray cHell out of the distributor, coil, plug wires, etc with .....tada ....WD40! Repeat every cold high humidity day until you can replace stuff.........

[snaxforgandhi]

Originally Posted by alchymist

Wow, you sure know a lot of big words......

Big words? This from someone whose username is Alchymist? Besides, the thread title was fair warning, right? Anyway, thanx for the advice. You sound like you must have seen this before? Is it fairly common? Again, thank you for your prompt reply!