This bulletin applies to 2008-2015 Buick Enclave vehicles equipped with a 3.6L engine. Some customers may comment about an engine misfire and check engine light with any or all cylinder misfires on deceleration. This may be the result of debris in the serpentine belt or balancer pulley, causing a jump and false misfire, and/or worn engine mounts causing a ground-out concern and false misfire.
Do not confuse this with normal roughness and a few random misfire counts that are “normal” on these engines at the same speeds in neutral or park.
Remove the accessory drive belt and drive or brake-stall at signature RPM. If the concern is gone, inspect the debris in the belt or pulleys. Use an engine lift to unload the engine mounts and brake-stall at signature RPM. If the concern is gone, inspect for a ground-out concern with the mounts.
