How to Do a Tune-Up on a Mitsubishi Montero

Replace the spark plugs. To get to the spark plugs, you will need to remove the engine cover as well as a number of parts. If you follow the thick black rubber tubes going into your engine and the spark plugs, you will see what needs to be removed. To remove them, you will need to remove a number of screws and components of the manifold. There are about 20 screws and bolts that need to be removed. You will also need to remove the EGR tube, the intake plenum, the vacuum line, the ground wire and the throttle cable. Consult a repair diagram for your exact model if necessary as it varies according to the specific year of the vehicle.

Once these components have been removed, you will see two rows of three black rubber spark plug boots. Start at the end of each row of spark plug wires and pull each one out, gripping the wire as close to the engine as possible. Once you have the boots off, use your spark plug wrench with extension to remove each spark plug. Simply slide the wrench over each one and loosen it until it can be easily removed.

Using your hands, insert each of the new spark plugs into their place and tighten. Use the wrench to finish tightening each one until they are snugly in place.

Replace distributor cap and rotor. Extract the other end of the spark plug wires from the coil terminals on the distributor cap. Set aside the wires to replace them with new wires. Unscrew the two screws holding the distributor cap and remove it. Next, pull the rotor straight off, noting the direction the rotor is pointing. Install the new rotor in the same position and direction. Place the new distributor cap and screw into place.

Replace spark plug wires. With the various engine components still removed, replace the old spark plug wires with new wires. Connect them at both ends, meaning at the distributor cap and onto the tops of the new spark plugs. Make sure both ends are connected tightly. Now replace all the component engine parts, bolts and screws from Step 1.

Replace the air filter. The air filter in your car should be replaced every 3,000 miles in addition to changing it during a tune-up. This will keep dirt from building up on your car's engine parts.

Locate the filter housing in front of the car's engine. It is connected to a the large black air intake tube, where the outside air comes into your vehicle. Remove the filter housing retainer clips. Simply remove the old filter and replace it with a new filter.