Tech Tips

Use this comprehensive information library whenever you need helpful hints from car repair professionals. Whether you are a professional or a DIY mechanic, you’re sure to find the tips you need to insure a job well done. Click here to go back to the previous page any time during your search.

Electrical System

Diagnosing Engine Problems from Looking at the Spark Plugs

All the components in an ignition system will leave revealing signs on the spark plugs, which are useful indicators about your engine problems. For example, a dry, soft, black carbon on the insulator and electrodes, called carbon fouling, is an indication that the ignition system is misfiring, or has faulty acceleration.

A burned center or blistered insulator is often a result of pre-ignition, which occurs when combustion begins before the timed spark fires. An extremely white insulator with small black deposits is an indication that the plug is overheating, which can be a result of the ignition timing being too advanced.

Go back