GM Service Manual Online
For 1990-2009 cars only

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.

    • Inspect the accessory drive system.
    • Repair or replace as required.

Loose or damaged crankshaft balancer

    • Inspect the crankshaft balancer.
    • Repair or replace as required.

Detonation or spark knock

Verify the correct operation of the ignition system. Refer to Detonation/Spark Knock.

Loose torque converter bolts

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

Loose or damaged flywheel

Repair or replace the flywheel.

Oil pump screen loose, damaged or restricted

    • Inspect the oil pump screen.
    • Repair or replace as required.

Oil transfer tube loose, damaged or restricted

    • Inspect the transfer tube.
    • Repair or replace as required.

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
    • 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 arrow or paint on the top of the piston facing the front of the engine. From the bottom, the squared pin boss must be toward the front of the engine.

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