Glossary / General

coil

48 Episode Mentions

Too Afraid to Ask

It’s a small device that turns the car’s battery power into a spark for each spark plug, which starts the engine.

Technical Definition

The coil, or ignition coil, steps up battery voltage to create the spark needed for combustion in each cylinder.

Hear It Discussed

"For example, you could have a bad coil, you could have a bad coil wire, you could have spark plug wires, you could have a bad plugs, bad distributor cap."
#2642: Overtightening Our Belts The Best of Car Talk 26:36

"You got them six months coils on there. You got to get the longer ones."
Save Money On Car Repairs With Our Car Talk Show Under The Hood show 34:39

"So they said, well, let's let's switch them back one more time, and we left the plugs where they were, switched the coils back one three and five for two, four and six, and they followed back over..."
Ron Ananian, The Car Doctor - May 9, 2026 - Hour 1 - Why Your Car Is Quietly Burning More Gas Ron Ananian The Car Doctor 20:55