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.

Loose and/or worn valve rocker arm attachments |

• | Inspect the valve rocker arm on the rocker arm shaft for looseness or excessive wear.

• | Repair or replace worn or damaged components as required.

Worn or damaged valve rocker arm |

• | Inspect the rocker arm for wear on the rocker arm adjusting screw tips or the cam riding surface.

• | Replace the valve rocker arms 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.) |

• | Inspect the accessory drive system.

• | Repair or replace as required.

Loose or damaged crankshaft pulley |

• | Inspect the crankshaft pulley.

• | Repair or replace as required. Refer to Crankshaft Pulley Replacement .

Detonation or spark knock | Verify the correct operation of the ignition controls system. Refer to Engine Controls.
Loose torque converter bolts |

• | Inspect the torque converter bolts and flywheel.

• | Repair or replace as required. Refer to Engine Flywheel Removal .

Loose or damaged flywheel | Repair or replace the flywheel. Refer to Engine Flywheel Removal .
Oil pump screen loose, damaged or restricted |

• | Inspect the oil pump screen.

• | Repair or replace as required. Refer to Oil Pan Replacement .

Excessive piston-to-cylinder bore clearance |

• | Inspect the piston and cylinder bore.

• | Repair as required.

Excessive piston pin-to-bore clearance |

• | Inspect the piston, piston pin, and the connecting rod.

• | Repair or replace as required.

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

• | The connecting rod bearings; refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .

• | The connecting rods; refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .

• | The crankshaft; refer to Crankshaft and Bearing Cleaning and Inspection .

• | The crankshaft journals; refer to Crankshaft and Bearing Cleaning and Inspection .

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

• | The crankshaft bearings; refer to Crankshaft and Bearing Cleaning and Inspection .

• | The crankshaft journals; refer to Crankshaft and Bearing Cleaning and Inspection .

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.) |

• | Verify the pistons, piston pins and connecting rods are installed correctly.

• | Repair as required. Refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .