Aurora 2001-2003

Diagnosis & Testing


There are two separate ignition module assemblies, one for each bank of cylinders. Each assembly contains an Ignition Control (IC) module and three ignition coils. Each IC module consists of the following circuits:

Ignition 1 voltage
IC timing low reference
IC control circuits for cylinders 1-6

Each ignition coil connects directly to its spark plug via a short boot. The IC circuits transmit timing pulses from the Powertrain Control Module (PCM) to the IC modules, which triggers the coils to fire the plugs in the correct sequence. The PCM monitors each IC circuit for improper voltage levels.

When servicing the ignition system components, use the following recommended procedures:

If a boot remains attached to a coil or a spark plug, twist the boot prior to removal. Use the J 43094 Spark Plug Boot Removal Tool.
Inspect the boot for a missing or damaged internal spring.
DO NOT re-install any component that has visible signs of damage.
Install the boots onto the coils until bottomed out. Then install the assembly onto the spark plugs. If this is not possible due to space limitations, just-start the boots onto the spark plugs and then install the coil assembly as straight down onto the plugs as possible.
Ensure that the boots are installed right side up.
Lift the module beauty cover at the end opposite the module to remove the cover.
Repair a torn perimeter seal with an RTV sealant.
Adhere to the torque specifications when installing the cassette to the cam cover and the module to the cassette.

The J 26792 Spark Tester (ST 125) presents a more difficult load on the secondary ignition than a normal spark plug. If a miss, a stumble, or a hesitation is being caused by a spark plug not firing, the spark tester should also not fire. A suspected ignition system miss may actually be a fuel system problem.