In 1985, Mitsubishi added the Mirage to its lineup, though Dodge sold a re-badged Mirage under the Colt name starting in 1979. The 1997 Mirage came in two trim levels: DE and LS. The DE trim level came fitted with a 92-horsepower, 1.5-liter engine and the LS came with a 113-horsepower, 1.8-liter engine. Mitsubishi recommended replacing the spark plugs on both engines every 30,000 miles. This basic maintenance ensures that the spark that ignites the gasoline in the engine is within the manufacturer’s specifications. A plug out of specification may lead to a rough running engine or poor fuel economy.
1. Check the gap on the bottom of all four new spark plugs, using a spark plug gap tool. Mitsubishi recommends a gap from 0.039 to 0.043 inches on the Mirage’s spark plugs. Adjust the gap as needed, using the spark plug gap tool.
2. Remove one spark plug wire from the engine, by grabbing the thick, rubber boot on the engine side of the wire and pulling up with a slight twisting motion.
3. Inspect the removed spark plug wire for any defects, such as: cracking, tearing, severe aging or brittleness. Replace the wires as a complete set if you detect any defects.
4. Remove the spark plug, using a ratchet, 6-inch extension and a spark plug socket. Remove the spark plug from the socket and insert a new spark plug into the socket.
5. Hand-tighten the new spark plug into the engine, using the spark plug socket and 6-inch extension. Connect a torque wrench to the extension and spark plug socket, and apply 15 to 21 foot-pounds of torque to the spark plug.
6. Coat the inside of the spark plug wire boot with a small amount of dielectric grease. Set the spark plug wire on the spark plug and press downward until the wire “clicks” onto the spark plug.
7. Repeat Steps 2 through 7 until you replace all four spark plugs.