GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Caprice WM 🢒 Engine 🢒 Engine Cooling 🢒 Lower Engine Noise, Regardless of Engine Speed

Cause

Correction

Low oil pressure.
  1. Perform an oil pressure test. Refer to Oil Pressure Diagnosis and Testing.
  2. Repair or replace damaged components as required.
    • Worn accessory drive components.
    • Abnormalities such as extreme 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.

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

Detonation or spark knock.

Verify the correct operation of the ignition controls system. Refer to Electronic Ignition (EI) System Diagnosis.

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

Loose or damaged engine flywheel.

Repair or replace the engine flywheel.

    • Damaged oil pan, contacting the oil pump screen.
    • An oil pan that has been damaged may incorrectly position the oil pump screen, preventing correct 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.

Piston-to-cylinder bore clearance above acceptable tolerances.
  1. Inspect the piston and cylinder bore.
  2. Repair as required.

Piston pin-to-bore clearance above acceptable tolerances.
  1. Inspect the piston, piston pin, and the connecting rod.
  2. Repair or replace as required.

Connecting rod bearing clearance above acceptable tolerances.

Inspect the following components, and repair as required:

    • The connecting rod bearings
    • The connecting rods
    • The crankshaft
    • The crankshaft journals

Crankshaft bearing clearance above acceptable tolerances.

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.