An often overlooked component of your car's engine is the set of spark plugs. Corroded spark plugs can indicate both major and minor problems in a car. It's important that you check your spark plugs regularly to see whether there is a buildup of black and crusty carbon.
A black, crusty buildup on the tip and electrode of the spark plug can result from the the plugs running with too much fuel. This causes carbon-fouling. The deposit is carbon-based and conductive, so the voltage will travel down the wrong path, causing an engine misfire and further carbon-fouling. Check for the correct plug heat range and fuel pressure specifications.
Bad wiring and leaking injectors can also cause black, crusty buildup. If your ignition system has weakened or failed, its inability to spark across the gap results in lower combustion chamber temperatures. This creates the black buildup.
If you drive at low speeds continuously, carbon may build up on the spark plugs. Changes in speed cleans the plugs through combustion. Maintaining low driving speeds all the time results in loss of the natural cleaning process.
