Diagnosis and Testing: Mechanical
WARNING: This page is about a different variant/trim than selected.
| CONDITION | POSSIBLE CAUSES | CORRECTIONS |
|---|---|---|
| NOISY VALVES | 1. High or low oil level in crankcase. | 1. Refer to Vehicle Quick Reference/Capacities and Recommended Fluids - Specifications . |
| 2. Thin or diluted oil. | 2. Change oil and filter. | |
| 3. Low oil pressure. | 3. Check oil pump, if Ok, check rod and main bearings for excessive wear. | |
| 4. Dirt in lash adjusters. | 4. Replace as necessary. | |
| 5. Worn rocker arms. | 5. Replace as necessary. | |
| 6. Worn lash adjusters | 6. Replace as necessary. | |
| 7. Worn valve guides. | 7. Replace cylinder head. | |
| 8. Excessive runout of valve seats on valve faces. | 8. See Engine/Cylinder Head/SEAL(S), Valve Guide - Description . | |
| CONNECTING ROD NOISE | 1. Insufficient oil supply. | 1. Refer to Vehicle Quick Reference/Capacities and Recommended Fluids - Specifications . |
| 2. Low oil pressure. | 2. Check oil pump, if Ok, check rod and main bearings for excessive wear. | |
| 3. Thin or diluted oil. | 3. Change oil and filter. | |
| 4. Excessive bearing clearance. | 4. Replace as necessary. | |
| 5. Connecting rod journal out-of-round. | 5. Replace crankshaft. | |
| 6. Misaligned connecting rods. | 6. Replace bent connecting rods. | |
| MAIN BEARING NOISE | 1. Insufficient oil supply. | 1. Refer to Vehicle Quick Reference/Capacities and Recommended Fluids - Specifications . |
| 2. Low oil pressure. | 2. Check oil pump, if Ok, check rod and main bearings for excessive wear. | |
| 3. Thin or diluted oil. | 3. Change oil and filter. | |
| 4. Excessive bearing clearance. | 4. Replace as necessary. | |
| 5. Excessive end play. | 5. Check thrust washers for wear. | |
| 6. Crankshaft journal out-of round. | 6. Replace crankshaft. | |
| 7. Loose flywheel or torque converter. | 7. Tighten to correct torque |