How do I know if I'm running too lean or rich?

[bull]

i have no idea 'where' the cone AF came from.

The ceramic color:

original- white

lean - white or almost white

proper - tan

rich - black

a proper running engine will take an overly rich plug and clean it to tan within about 500 miles of driving.

[coreyman]

Originally Posted by bull

i have no idea 'where' the cone AF came from.

The ceramic color:

original- white

lean - white or almost white

proper - tan

rich - black

a proper running engine will take an overly rich plug and clean it to tan within about 500 miles of driving.

Thanks I'll need to get a new plug to properly test this I'm assuming.