Frequently Asked Questions
Q: How often should I replace my spark plugs?
Q: How do I choose the right spark plug?
Q: How do I "read" a spark plug?
Q: How much of a performance improvement can I expect from changing plugs?
Q: What is a "fouled" spark plug?
Q: Do I need to set the "gap" when installing a new set of plugs?
Q: Are special plugs always necessary on a modified engine?
Q: How do I install spark plugs correctly?
Q: When should I use a resistor spark plug?
Q: Why are there different heat ranges?
Q: What do the numbers and letters in a part number represent?
Q: Does humidity affect spark plug temperature?
Q: Does ignition timing affect a spark plug's temperature?
Q: Does compression ratio affect firing end temperature?
Q: Can old spark plugs be cleaned?
Q: What is the maximum I can open or close the gap?
Q: What is pre-ignition?
Q: What is detonation?