The ignition system consists of the following components or circuits:

The crankshaft position (CKP) sensor is a magneto resistive type sensor. The CKP sensor works in conjunction with a 24X reluctor wheel. The reluctor wheel is mounted on the rear of the crankshaft. The 24X reluctor wheel uses 2 different width notches that are 15 degrees apart. This pulse width encoded pattern allows cylinder position identification within 90 degrees of crankshaft rotation. In some cases this can be achieved within 45 degrees of crankshaft rotation. The reluctor wheel also has dual track notches that are 180 degrees out of phase, this design allows for quicker starts and accuracy. The CKP sensor also outputs a 4x signal for spark control, misfire diagnosis, tachometer output, and fuel control. All CKP signals are output as a digital square waveform.

The camshaft position (CMP) sensor works in conjunction with 1X reluctor wheel mounted at the rear of the camshaft. The CMP is used to determine the top dead center position of cylinder #1, and will synchronize with the 24X CKP sensor signal for quicker starting. The PCM will detect an increase in the mass airflow (MAF) sensor signal when the engine starts. The CMP signals are output as a digital waveform.

The ignition system on this vehicle features a multiple coil configuration and is known as coil near plug. There are two styles of ignition coil assemblies (1,2). The engine could have either style. The ignition coil mounting bracket is attached to the rocker cover (3).

The 8 ignition coils are individually mounted above each cylinder on the rocker covers. The coils are fired sequentially. There is an ignition control (IC) circuit for each ignition coil . The 8 ignition control circuits are connected to the PCM. The PCM triggers each ignition coil individually and makes all timing decisions. The ignition coils are supplied with the following circuits:

The ignition 1 voltage circuits are fused separately for each bank of the engine. The 2 fuses also supply the power for the injectors for that bank of the engine. Each coil is serviced separately.

This system puts out very high ignition energy for plug firing. Less energy is lost to ignition wire resistance because the ignition wires are much shorter than in a conventional ignition system.

To properly control ignition timing, the PCM relies on the following information:

The ignition control (IC) system consists of the following components:

The ignition control utilizes the following to control spark timing functions:

There are important considerations to point out when servicing the ignition system. The following noteworthy information will list some of these to help the technician in servicing the ignition system.

The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. To provide optimum driveability and emissions, the PCM monitors input signals from the additional following components in calculating ignition control (IC) spark timing: