The 2003 Buick LeSabre was fitted with a 205-horsepower, 3.8-liter V-6 engine. The 3.8-liter V-6 engine is a widely used engine in General Motors' lineup, it has been used in the Chevrolet Monte Carlo, Pontiac Grand Am, Pontiac Grand Prix and the Buick Park Avenue. The 3.8-liter has also been used as a performance engine in the Grand Prix GTP, in which it was supercharged. Buick recommends the spark plugs be changed every 12,000 miles if you drive in stop-and-go traffic. The interval extends to every 30,000 miles if you primarily drive on the highway.
Open the LeSabre's hood and remove the oil filler tube by twisting it counterclockwise and pulling it from the engine. Remove the upper engine cover by pulling it up and off of the engine.
Pull one spark plug wire from the engine, by grabbing the wire's boot with your hand and twisting the wire as you pull.
Loosen and remove the spark plug below the removed spark plug wire, using a ratchet and spark plug socket. On the rear plugs, you'll need a swivel socket adapter to access the plugs.
Check the spark plug gap, using the spark plug gap tool. The gap must be 0.60 inche. Adjust the gap as needed with the spark plug gap tool.
Install the new spark plug until it is hand-tight, using a spark plug socket and a 6-inch socket extension. Start the plug by hand. Tighten the spark plug to 11 foot-pounds, using a torque wrench and the 6-inch socket extension.
Trace the removed spark plug wire back to the ignition coil and pull it from the coil, by grabbing the wire's boot and twisting as you pull it off. Match the old wire with the new wire of the same length, and replace it.
Repeat Steps 2 through 6 for all six spark plugs and wires around the 3.8-liter engine.
Place the engine cover back in place on top of the engine. Put the oil filler tube back on top of the engine and twist it clockwise to lock it and the cover in place.
