See Figure 1
When it is suspected that one or more spark plugs may not be firing and the spark plug wires do not seem to be at fault, this test offers a quick check to see if the ignition module and coil packs are producing spark voltage.
- Turn the ignition to the OFF position, then tag and disconnect all 4 spark plug wires from the ignition module towers.
- Make sure that you are not touching the vehicle, then have an assistant crank the engine for a few seconds. Sparks should appear alternately between each pair of ignition coil towers while the engine is cranking.
Do not crank the engine for more than a few seconds at a time or starter damage may occur. Crank the engine for a few seconds, then release the ignition key and pause for an equal amount of time before cranking the vehicle again.
- If sparks appear between the 2 towers, the DIS module, Crankshaft Position Sensor (CPS) and the ignition coil packs are known to be good.
- If a single coil pack is suspect from an initial spark test, or no sparks appeared between its 2 towers, switch the coil pack to the opposite position on the ignition module (the coil packs are interchangeable) and check to see if the problem follows it. If the problem follows, the coil pack must be replaced. If the formerly good coil pack does not produce spark when switched with the suspect coil on the module, and the suspect coil works in the new position, then the ignition module is bad and must be replaced. Also, using an ohmmeter, check the resistance across the suspect coil' towers; it should be 7,000-10,000 ohms.
- If no spark can be found across any tower, proceed with the NO SPARK TEST.
REMOVAL & INSTALLATION
See Figures 2, 3, 4 and 5
- Properly disable the SIR system, if equipped, and disconnect the negative battery cable.
- Label and disconnect the spark plug wires from the DIS ignition module located on the front side of the bell housing.
- Unfasten the electrical connectors from the ignition module.
- Remove the 4 retaining bolts and the DIS unit.
- If necessary, the coils may be removed from the unit at this time by using a pair of needlenose pliers to squeeze the retaining tabs while pulling the coils upward.
- If removed, install the coils to the ignition module by aligning the coils with the module terminals, then carefully guiding the coils into position.
- Run a 6 x 1.0mm tap through the module mounting holes on the bell housing to remove any remaining thread sealant residue and verify that the module and bell housing mating surfaces are clean and free from grit or dirt.
- Always use new module mounting bolts. Install the ignition module/coil assembly using the new bolts equipped with factory applied thread sealant and tighten the bolts to 61 inch lbs. (7 Nm) using a torque wrench. Be careful when tightening the mounting bolts, and verify that each bolt head is properly seated on the module unit when tightened. If a bolt is not properly seated when the torque reaches the proper specification, remove the bolt and clean the bore threads again using the tap.
- Attach the electrical connectors and spark plug wires to the module unit. Make sure the spark plug wires are properly connected to avoid engine damage.
- Connect the negative battery cable and, if equipped, properly enable the SIR system.
- Start the engine and check operation.