Spark plug is one of the most important parts of any car, if it is in good condition the car engine will run smoother and will return higher fuel economy, but if it has a problem your car will not run softly and the economy will also not be that good. The engine will misfire or hesitate on acceleration.
Now the thing is how well you know your car and the problems that might come up. First of all you need to know what a normal spark plug looks like and what its condition should be. A “normal” plug should have brown to greyish tan colour with the electrode slightly worn off. It will have correct operating condition and the heat range for the engine is right. It is highly recommended that whenever you change the spark plugs; replace them with ones having the same heat range LS swap part.
Now the condition of a problematic spark plug will be easily identified as you know how a normal one should look like. There is a condition called “Carbon Deposits” where the plugs have dry sooty deposits on them which indicates there might be rich mixture or the ignition is weak. It causes the engine hard starts or misfires and hesitates. The recommendation is to check for a clogged air cleaner, sticky choke, high float level and worn ignition points. The use of a longer core nose spark plug would give greater anti-fouling protection.