For 1990-2009 cars

Cause | Correction
--- | ---
Low oil pressure |

• | Perform an oil pressure test. Refer to Oil Pressure Diagnosis and Testing.

• | Repair or replace damaged components as required.

Worn accessory drive components--Abnormalities, such as severe cracking, bumps, or missing areas in the accessory drive belt and/or misalignment of system components |

1. Inspect the accessory drive system.
2. Repair or replace as required.

Leaking and/or sticking fuel injection nozzle--A stuck fuel injection nozzle can cause a noise similar to a damaged piston, rod or rod bearing. |

1. Use the cylinder balance diagnostic procedure to help locate the cylinder that is the source of the noise.
2. If you cannot locate the cylinder that is the source of the noise, diagnose the engine for mechanical damage.
3. If it has been determined that the fuel injection nozzle is causing the noise, replace the fuel injection nozzle.

Loose or damaged crankshaft balancer |

1. Inspect the crankshaft balancer.
2. Repair or replace as required.

Loose torque converter bolts |

1. Inspect the torque converter bolts and flywheel.
2. Repair or replace as required.

Loose or damaged flywheel | Repair or replace the flywheel.
Damaged oil pan, contacting the oil pump screen--An oil pan that has been damaged, may improperly position the oil pump screen, preventing proper oil flow to the oil pump. |

1. Inspect the oil pan.
2. Inspect the oil pump screen.
3. Repair or replace as required.

Oil pump screen loose, damaged or restricted |

1. Inspect the oil pump screen.
2. Repair or replace as required.

Excessive piston-to-cylinder bore clearance |

1. Inspect the piston and cylinder bore.
2. Repair as required.

Excessive piston pin-to-bore clearance |

1. Inspect the piston, piston pin, and the connecting rod.
2. Repair or replace as required.

Misaligned or bent connecting rod |

1. Inspect connecting rod and connecting rod bearings.
2. Repair or replace all damaged components.

Excessive connecting rod bearing clearance | Inspect the following components, and repair as required:

• | The connecting rod bearings

• | The connecting rods

• | The crankshaft

• | The crankshaft journals

Excessive crankshaft bearing clearance | Inspect the following components, and repair as required:

• | The crankshaft bearings

• | The crankshaft journals

Incorrect piston, piston pin, and connecting rod installation--Pistons must be installed with the mark or dimple on the top of the piston, facing the front of the engine. Piston pins must be centered in the connecting rod pin bore. |

1. Verify the pistons, piston pins and connecting rods are installed correctly.
2. Repair as required.

Oil pump pickup tube or screen bent or loose |

1. Inspect the oil pump pickup tube and/or screen.
2. Repair or replace all damaged components.