PISTON SCUFFING ON 3.1L ENGINE (REPLACE PARTIAL ENGINE ONLY). Chevrolet Beretta 1991

For 1990-2009 cars

# PISTON SCUFFING ON 3.1L ENGINE (REPLACE PARTIAL ENGINE ONLY)

#### Subject: PISTON SCUFFING

#### Model and Year: 1990 CAVALIER, CORSICA, BERETTA AND LUMINA WITH 3.1L ENGINE 1990 LUMINA (APV) WITH 3.1L ENGINE

Condition: Some 1990 J, L and W cars and U-vans (APV) may exhibit engine piston scuffing, which could result in cold engine knock at low ambient temperatures. This condition will not lead to engine failure and is limited to cylinders #2, #4 and #6.

Cause: Premature wear of the pistons due to low adhesion of the tin plating.

Correction: If pistons need replacement due to scuffing, a partial engine replacement is HIGHLY recommended rather than replacement of individual pistons. This recommendation is made since other pistons in these engines might have to be replaced later.

Labor Operation Number: J 1820

Labor Time: Use applicable time

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