Pulling the Plugs
Removing the plugs while the engine is hot can damage the plugs and the head due to differing rates of thermal expansion. Always wait until the engine is cold. While there is not a set temperature, take your time and use your best judgment.
Incorrectly removing or installing spark plugs can cause damage to your engine. Also, care needs to be taken when removing spark plug wires, especially if you plan to reuse them. It's possible to damage the threads inside the engine when installing the spark plug.
If available, use compressed air to blow any dirt or debris away from the cylinder before spark plug removal. Unscrew each spark plug with the spark plug socket and remove one spark plug at a time. Check each spark plug when removing. If the tip is brown or grayish, the engine is running properly.
A leading cause of spark plug problems is a flow of engine oil into the combustion chamber. If oil leaks into the combustion chamber, it can cause the tip of the spark plug to get oily and dirty leading to premature failure.
Most cars need them done at 30,000 to 60,000 miles, while others are good until 100,000 miles. The most important thing to remember is to change the wires when you do the spark plugs.
The greatest benefit of changing your spark plugs is that your engine will run better, provide you with improved gas mileage, and may reduce the pollution from the vehicle. It is a reasonable cost to replace the spark plugs, as well.
If you're a handy person and want to tackle changing spark plugs on your own, you can save on the labor. It will likely take between one and two hours to get the tune-up done and only requires basic tools like a socket set.
The most common signs of bad spark plugs include start-up trouble, rough idling, sluggish acceleration, declining fuel economy, engine misfiring, and engine knocking.
Many factors can cause a spark plug to fail; from incorrect heat ranges to improper gapping, to chemical contamination. Yet 90% of spark plug damage claims are due to improper torque. Many factors can cause a spark plug to fail; from incorrect heat ranges to improper gapping, to chemical contamination.
Tighten the spark plug finger-tight until the gasket reaches the cylinder head, then tighten about ½ – ⅔ turn more with a spark plug wrench. (Taper seat: About 1/16 turn more.)
Lubricate Spark Plugs & Other Parts
For part of your car repair and maintenance, you can use WD-40 to remove carbon residue, and keep moisture away from spark plugs and spark plug wires. “WD” stands for Water Displacement.
You'll want to wait at least 30 minutes before installing new spark plugs. That should give the engine adequate time to cool down.
2. Make Sure the Engine Is Cold. A hot engine can burn your skin. On top of that, changing a spark plug with a warm engine head can damage the threads that hold it in place.
However, having oil on your spark plug threads or in your plug wells for a prolonged period is a serious problem that can result in a misfire, increased oil consumption, and increased fuel consumption. It can even lead to engine damage and destroy components like your catalytic converter.
Overtightening the plugs can cause the shell of the plug to stretch, which will break the gas seals and lead to pre-ignition, or detonation. Furthermore, too much torque can cause the ceramic insulator to become loose in the metal shell and possibly eject from the cylinder head while the engine is running.
To answer your question in one word - YES, the wrong spark plugs or incorrect spark plug gap can and often will cause a vehicle's engine to misfire or run incredibly inefficient.
bad spark plugs can cause your engine to misfire. the engine's computer uses sensors to detect these misfires and will create a code that turns on the check engine light. a flashing check engine light indicates the misfire is severe enough to cause damage to your catalytic converter.
If a spark plug or multiple spark plugs are faulty, they will have trouble creating the spark that causes the ignition process in your vehicle. This results in your vehicle having trouble starting, hesitating or having issues with accelerating properly.