For 1990-2009 cars

• | Improper oil viscosity. Install recommended oil viscosity for expected temperatures.

• | Excessive piston to bore clearance.

• | Excessive piston pin to piston clearance.

• | Excessive crankshaft end clearance.

• | Excessive crankshaft bearing clearance.

Some engine noise may be normal for 1-3 seconds at start-up. Be sure that any noise that is identified is really coming from the engine. (i.e. ABS initialization noise)