To determine if a faulty MCM is causing the cylinder to misfire, perform the following:
1. Remove the thru-bolts holding the MCM to the engine; refer to the appropriate service manual, fuel system chapter.
2. Remove the MCM from the engine and tag the MCM for core return.
3. Obtain a new reprogrammed MCM.
4. Inspect the MCM isolators for any damage. Replace if necessary, refer to the appropriate service manual, fuel system chapter.
5. Install the MCM to the engine using thru-bolts; refer to the appropriate service manual, fuel system chapter.
6. Torque the MCM thru-bolts to 23 – 27 N·m (17 – 20 lb·ft).
7. Install the 120–pin Engine Harness connector to the MCM.
3.4.1
Faulty MCM Repair
No repair authorized for MCM.
3.4.1.1
Verification of Repair for Faulty MCM
Perform the following steps to determine if the new MCM resolved the misfiring cylinder condition:
1. Start the engine.
2. Run the engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
[a] If the engine is not misfiring, shut down the engine. No further troubleshooting is required.
[b] If the engine is misfiring, shut down the engine and check for worn or damaged valves and cylinder kits; refer to section 3.5.
