How to Replace Spark Plugs in a 6.8L Engine
- 1). Remove the wire from the top of the spark plug. Do this by gripping firmly on the wire connector and pulling straight up.
- 2). Use your ratchet and spark plug socket---a socket designed specifically for removing spark plugs from an engine---and loosen the spark plug in its socket. Do not turn the plug more than twice.
- 3). Clean the area around the spark plug until it is free of dirt and grime. This is crucial, because if even a small piece of dirt falls into the spark plug hole, your engine can be extensively damaged. Once the area is clean, finish unscrewing the spark plug. Once the plug is out, you may discard it.
- 4). Place the new spark plug in the hole and screw it in until it is hand-tightened, then use your ratchet to tighten it down. Depending on the type of spark plug you used, you will want to tighten it differently. If your spark plug is a gasket-type plug, give the plug a 1/4 (90-degree) turn from the point of hand-tightening. If your spark plug is a tapered seat plug, give it a 15-degree turn from the point of hand-tightening.
- 5). Repeat steps 1 through 4 for the rest of the spark plugs.
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