Ignition System: Service and Repair

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 ignition coils secondary voltage output capabilities are very high more than 40,000 volts. Avoid body contact with ignition high voltage secondary components when the engine is running, or personal injury may result!

^ The 7X crankshaft position sensor is the most critical part of the ignition system. If the sensor is damaged so that pulses are not generated, the engine may not start!

^ Crankshaft position sensor clearance is very important! The sensor must not contact the rotating interrupter ring at any time, or sensor damage will result. If the balancer interrupter ring is bent, the interrupter ring blades will destroy the sensor

^ Ignition timing is not adjustable. There are no timing marks on the crankshaft balancer or timing chain cover.

^ If crankshaft position sensor replacement is necessary, the crankshaft balancer must be removed first. The balancer is a press fit onto the crankshaft, removing the serpentine accessory drive belt and balancer attaching bolt will allow its removal with special tool J 38197. When reinstalled, proper torquing of the balancer attachment bolt is critical to ensure the balancer stays attached to the crankshaft.

^ If a crankshaft position sensor assembly is replaced, check the crankshaft balancer interrupter ring for any blades being bent. If this is not checked closely and a bent blade exists, the new crankshaft position sensor can be destroyed by the bent blade with only one crankshaft revolution.

^ Neither side of the ignition coil primary or secondary windings is connected to engine ground. Although the ignition coil packs are secured to the ignition control module, it is not an electrical connection to ground.

^ Be careful not to damage the secondary ignition wires or boots when servicing the ignition system. Rotate each boot to dislodge it from the plug or coil tower before pulling it from either a spark plug or the ignition coil. Never pierce a secondary ignition wire or boot for any testing purposes! Future problems are guaranteed if pinpoints or test lights are pushed through the insulation for testing.

^ The ignition control module is grounded to the engine block through 3 mounting studs used to secure the module to its mounting bracket. If servicing is required, ensure that good electrical contact is made between the module and its mounting bracket, including proper hardware and torque.

^ A conventional tachometer used to check RPM on a primary ignition tach lead will not work on this ignition system. In order to check RPM, use a Scan Tool.