spark plug colour

[jddevel]

Strange question but how soon into a drive should one expect the electrodes to be their correct brown or light grey colour.

[Steve Simmons]

I would think pretty quickly, provided a large change from rich to lean wasn't made. I'm just guessing but I would feel pretty confident about 5-10 miles. And be sure to shut the car down immediately, as idling usually results in darkening the plugs.

[jddevel]

Thanks Steve.