An engine vacuum leak from the throttle-body base gasket may result in a rough idle and/or stumble on acceleration. If this occurs, replacement of the failed gasket will be necessary.

Some Buick LaCrosse owners report experiencing slow acceleration due to various potential issues, including clogged air filters, dirty mass air flow sensors, and clogged fuel filters. These problems can lead to sluggish starts and delayed responses when pressing the accelerator. Additionally, some owners have noted that jerking during acceleration may indicate a misfire, while reduced engine power in 2010 models can sometimes be improved by applying electric grease to the throttle body connector and gas pedal assembly electrical connectors. Furthermore, a weak battery or malfunctioning alternator may also contribute to acceleration problems. It is crucial for owners to consider these factors to effectively diagnose and resolve slow acceleration issues in their Buick LaCrosse.