Diagnosis & Testing
- Turn the ignition off.
- Remove the ignition coil.
- Install a spark tester(s) to the ignition coil.NOTEOn the 2.7 and 3.5L engines, cylinders 1, 3 and 5, it is necessary to remove the upper intake to access the ignition coils. Once the ignition coil has been removed from the cylinder head, the intake must be reinstalled to be able to crank the engine. Move the ignition coil harness connector through the slots in the upper intake and then connect the coil to the harness connector. Secure the upper intake to the lower intake in accordance with the service information.
- While cranking the engine observe the spark coming from the spark tester.NOTEA crisp blue spark that is able to jump the gap of the spark tester should be generated.
- Turn the ignition off.
- Disconnect the Ignition Coil harness connector.
- Ignition on, engine not running.
- With a scan tool, actuate the ASD Relay.
- Using a 12-volt test light connected to ground, probe the (K343) ASD Relay Output 2 circuit in the Coil on Plug harness connector.
- If the test light doesn-t illuminate brightly
- Repair the open or short to ground in the (K343) ASD Relay Output 2 circuit between the IPM and Coil harness connector.
- If the test light illuminate brightly check the ignition coil resistance.
- Turn the ignition off.
- The following resistance measurement should be taken at 70°-80° F.
- Measure the resistance of the Ignition Coil.
- If the resistance is not between 0.53 to 0.65 ohms at 77°F (25°C) for the Ignition Coil being tested replace the Ignition Coil.
- If the resistance is between 0.53 to 0.65 ohms at 77°F (25°C) for the Ignition Coil being tested:NOTEBefore continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.WARNINGDo not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.NOTEBefore continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.Using a 12-volt test light connected to a 12-volt source, probe the (K19) Coil Control No.1 circuit.Crank the engine for 5 seconds while observing the test light.If the test light is brightly blinking while cranking the engine replace the Ignition Coil.If the test light is ON constantly while cranking the engine check for (K19) coil control no. 1 circuit shorted to ground.Turn the ignition off.Disconnect the C2 PCM harness connector.Measure the resistance between ground and the (K19) Coil Control No.1 circuit in the Ignition Coil harness connector.If the resistance is below 100 ohms repair the short to ground in the (K19) Coil Control No.1 circuit.If the resistance is above 100 ohms, using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.If there were any problems found repair as necessary.If there were no problems found, replace and program the Powertrain Control Module per Service Information.If the test light is OFF constantly while cranking the engine. Inspect for (K19) coil control no.1 circuit open.Turn the ignition off.Disconnect the C2 PCM harness connector.Measure the resistance of the (K19) Coil Control No.1 circuit from the Ignition Coil harness connector to the appropriate terminal of special tool #8815.If the resistance is above 5.0 ohmsRepair the open in the (K19) Coil Control No.1 circuit.If the resistance is below 5.0 ohms using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.If there were any problems found repair as necessary.If there were no problems found, replace and program the Powertrain Control Module per Service Information.
Ignition Coil
Removal & Installation
2.7L, 3.2L & 3.5L Engines
- Disconnect negative battery cable.
- Remove the intake manifoldNOTEPrior to removing the ignition coils, spray compressed air around the coil area and spark plug.
- Remove electrical connector from ignition coil.
- Remove 2 fasteners from ignition coil assembly.NOTEOn 3.5L engines, it is necessary to loosen the screws by alternating back and forth.NOTEDo not lose the spacers under the coil when loosening the screws.
- Remove ignition coil assembly.
To install:
- Install or connect the following:NOTEOn 2.7L engine to 55 inch lbs. (6.2 Nm)NOTEOn 3.5L engines to 60 inch lbs. (6.7 Nm)NOTEOn 3.5L engines, it is necessary to tighten the screws by alternating back and forth.WARNINGDo not lose the spacers under the coil when installing ignition coils.Install ignition coil assembly to spark plug.Install coil screws and tighten.
- Connect the electrical connector and lock.
- Install the intake manifold
- Connect negative battery cable.
Firing Orders
Spark Plugs
Inspection & Gapping
Check the plugs for deposits and wear. If they are not going to be replaced, clean the plugs thoroughly. Remember that any kind of deposit will decrease the efficiency of the plug. Plugs can be cleaned on a spark plug cleaning machine, which can sometimes be found in service stations, or you can do an acceptable job of cleaning with a stiff brush. If the plugs are cleaned, the electrodes must be filed flat. Use an ignition points file, not an emery board or the like, which will leave deposits. The electrodes must be filed perfectly flat with sharp edges; rounded edges reduce the spark plug voltage by as much as 50%.
Check spark plug gap before installation. The ground electrode (the L-shaped one connected to the body of the plug) must be parallel to the center electrode and the specified size wire gauge (please refer to the Tune-Up Specifications chart for details) must pass between the electrodes with a slight drag. NEVER adjust the gap on a used platinum type spark plug.
Always check the gap on new plugs as they are not always set correctly at the factory. Do not use a flat feeler gauge when measuring the gap on a used plug, because the reading may be inaccurate. A round-wire type gapping tool is the best way to check the gap. The correct gauge should pass through the electrode gap with a slight drag. If you're in doubt, try one size smaller and one larger. The smaller gauge should go through easily, while the larger one shouldn't go through at all. Wire gapping tools usually have a bending tool attached. Use that to adjust the side electrode until the proper distance is obtained. Absolutely never attempt to bend the center electrode. Also, be careful not to bend the side electrode too far or too often as it may weaken and break off within the engine, requiring removal of the cylinder head to retrieve it.
2.7L, 3.2L And 3.5L Engines
The V6 engines use platinum resistor spark plugs.
- Disconnect the negative battery cable.
- Remove the intake manifold.NOTEPrior to removing the ignition coils, spray compressed air around the coil area, spark plug and spark plug tube.WARNINGOn 3.5L engines, it is necessary to loosen the screws by alternating back and forth. Do not lose the spacers under the coil when loosening the screws.
- Remove the ignition coil.
- Remove the spark plug using a quality socket with a rubber or foam insert.
- Inspect the spark plug condition.
To install:
- Install or connect the following:WARNINGTo avoid cross threading, start the spark plug into the cylinder head by hand.NOTEOn 2.7L Engines Tighten to 12.5 ft. lbs. (17 Nm).NOTEOn 3.5L Engines Tighten to 20 ft. lbs. (28 Nm).Tighten spark plugs.Install ignition coil assembly onto spark plug.Hand tighten coil screws.Tighten ignition coil screws to 60 inch lbs.( 6.7 Nm).Connect and lock the electrical connector.Install the intake manifoldConnect the negative battery cable.
Inspection
Removal & Installation
2.7L Engine
- Remove or disconnect the following:Negative battery cable from the remote ground postBattery feed and posi-lock connectorsNuts from the catalyst support bracket and mountStarter heat shield3 starter-to-engine/transaxle boltsStarter by rotating it toward the engine and sliding it rearward between the catalyst and the engine mount
To install:
- Install or connect the following:Starter by sliding it forward between the catalyst and the engine mount and rotating it away from the engineStarter and torque the 3 starter-to-engine/transaxle bolts to 40 ft. lbs. (54 Nm)Starter heat shieldNuts to the catalyst support bracket and mountPositive battery cable and torque the nut to 89 inch lbs. (10 Nm)Posi-lock connectorsNegative battery cable to the remote ground post
- Remove or disconnect the following:Negative battery cable from the remote ground postStarter-to-engine/transaxle nut and boltsPositive battery feed wire from the starterStarter and position it to gain access to the posi-lock connector
- Place a support under the engine and slightly relieve the pressure from the left engine mount.
- Remove the 3 left engine mount-to-engine bolts.
- Slightly, raise the engine to provide more room.
- Remove the starter by sliding it rearward between the catalyst and the engine mount.
- Remove the posi-lock connector.
To install:
- Install or connect the following:Posi-lock connectorStarter by sliding it forward between the catalyst and the engine mount
- Slightly, lower the engine.3 left engine mount-to-engine boltsPositive battery feed wire to the starter and torque the nut to 89 inch lbs. (10 Nm)Starter and torque the starter-to-engine/transaxle bolts to 40 ft. lbs. (54 Nm)Negative battery cable to the remote ground post