Different engine noises that are heard when a problem occurs are listed in the following table.
| Type of Noise | Check the Following: |
| Whining Noise | Gear Train, refer to “13.1.1 Check Gear Train” . |
| Whistling Noise | Air intake including the CAC and all hoses |
| Turbo clamps | |
| Gaskets in exhaust system | |
| Internal turbo damage | |
| Low Pitch Knock | Rod bearings |
| Pistons | |
| Wrist pin | |
| High Pitch Knock/Squeal | Valve train damage |
| Fuel system problems | |
| Belt accessory drive | |
| Belt tensioner | |
| Alternator | |
| A/C compressor | |
| Water pump |
Check Gear Train
A whining noise indicates a problem with the gear train.
Check as follows:
- Pull the engine
- Drain the engine oil.
- Pull the oil pan.
- Move the doser feed line.
- Remove the Crankcase Position (CKP) Sensor.
- Remove the fuel pump gear plate.
- Remove the flywheel housing.
- Inspect the gears for damage.
- Inspect the thrust washers and gear bushings for damage.
- Check the gear lash.
