The Pros & Cons Of Hotter Vs. Colder Spark Plugs

You might not think about spark plug heat ratings often, so here's a rundown on what that means and how it affects your ...
Ars Technica

Fouled plugs, bad gas, how to best deal with the gas tank?

Subject says it all. An old 70's Toyota pickup, for my SO's daughter to use to get to archeological dig site. Bought for a pittance with only 74K, it got home OK, but didn't run after that. I know it ...
JSTOR Daily

Plug Fouling Investigations on a Running Engine - An Application of a Novel Multi-Purpose Diagnostic System Based on the Spark Plug

SAE Transactions, Vol. 100, Section 4: JOURNAL OF FUELS & LUBRICANTS (1991), pp. 681-686 (6 pages) A method for non-intrusive measurement of spark plug fouling, burn quality, pre-ignition and spark ...