Lower Engine Noise, Regardless of Engine Speed

WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

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 Symptoms - Engine Controls .
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.
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.	Inspect the oil pan. Inspect the oil pump screen. Repair or replace, as required.
Oil pump screen loose, damaged, or restricted	Inspect the oil pump screen. 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 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.