Re: changing spark plugs
It shouldn't score the cylinder walls - you should take the head off and clean out the cylinders before you start the engine. I learned that the hard way on an old Dodge. My newer Dodge is the same, along with the Taurus. Even when I wash the engine I'll dab out the water buildup with a cloth. I hate changing plugs on a transverse engine - just the ones on the inner bank!
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!