Prowler V6-3.5L VIN G (1999)
Spark Plug: Testing and Inspection
Cold or Carbon Fouling
COLD FOULING (CARBON FOULING)
Normal Operation And Cold(Carbon) Fouling
Cold fouling is sometimes referred to as carbon fouling because the deposits that cause cold fouling are basically carbon. A dry, black deposit on
one or two plugs in a set may be caused by sticking valves or misfire conditions. Cold (carbon) fouling of the entire set may be caused by a
clogged air cleaner or poor ignition output.
Cold fouling is normal after short operating periods. The spark plugs do not reach a high enough operating temperature during short operating
periods. Replace carbon fouled plugs with new spark plugs.