Timing Belt Change -- Page 5
Replacing Cam Seals & Alternator
Replacing PCV Valve
Waterpump and Thermostat
Replace Timing Belt and ReAssembly
Timing Belt Change -- Page 2
Timing Belt Change -- Page 3
Timing Belt Change -- Page 4
Changing the Spark Plugs
Timing Belt Change -- Page 1
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Mitsubishi 3.0 SOHC Engine

Changing the Spark Plugs

Make sure that if you are planning to change the timing belt, that you leave the spark plugs in place until you "bump" the starter as described in that section.

First make sure the battery is disconnected, and the center wire from the ignition coil is also off. Start by removing the intake and airbox lid as shown below.



With the filter out, you can see the PCV vent box (oval), which circulates air from the PCV system to the atmosphere. Make sure this filter is clean and the PCV tubing is clear.

Remove the mounting bolts and take out the airbox. Note the tubing connecting to the PCV vent system at the L rear.



Now you are ready for the plugs. Label the wires at the distributor and at the end of each wire if you have not already done so. At this point, the right-most rear plugs (# 3 & 5) and the front plugs (# 2,4,6) are easy to access. Use a standard spark plug socket plus extension to remove them.

Number # 1 plug will be difficult unless you have already removed either the intake plenum (not this job) or the alternator and/or its bracket. Take your time.



Gap the new plugs correctly, and apply anti-seize to each before re-installation. Here is a table for several Chrysler engines, as well as the timing settings.


Re-check the plug & distributor wires, & make sure that the center plug is connected to the ignition coil. Re-assemble the airbox, remembering to re-connect the PCV hoses. Re-connect the battery for re-start


if the engine does not run smoothly, check for a loose wire at the plug or distributor site. You can also check to make sure each plug is correctly seated. Don't strip these plug threads, and torque gently (only a little tight is fine). The plug wires need to be fully seated or they may not fire (#1 is prone to this, as it is hard to get to).


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