How I eliminated my misfires for next to nothing

[Eggbert]

Though interesting, in hindsight not surprising, is how I cured my misfire problem very cheaply. Every so often I get misfires with the Cobra. Generally replacing wires and plugs fixes the problem. Last time I realized that the plugs wern't very old, nor were the wires, so I wondered what was going on.

I keep my Cobra in an unheated garage with a cement floor and cement walls 1/2 way up. The car sits there all winter and during the warmer weather only gets used about once a week. It's undoubtedly a high humidity area. So I speculated, and based on my results I suspect I'm right. Maybe that part is surprising!

My theory is that condensation forms on the exposed part of the spark-plug porcelain and slowly migrates up under the wire boot. This eventually allows a path for the spark to leak out which is more noticeable the harder you push the engine. This doesn't happen with my daily driver as the daily application of engine heat evaporates the condensation before it has time to travel up under the boots.

So I took my badly misfiring engine and removed the plugs and the wires from the plug ends only. I cleaned the porcelain with Brake Klean and then rubbing alcohol and then swabbed dielectric grease over the porcelain part of each plug, but not the metal tip where the boot fits. I also cleaned inside the boots the same way and using a Q-Tip swabbed the inside of the boots with the grease as well.

That was in the Fall, though I'm not sure if that was last year or the year before, but anyway no more misfires since.

I never bothered using dielectric grease before, but as previously mentioned, probably never had to for my daily driver.

Saved me money on these: