Where is the vacuum modulator in a 1999 Pontiac Montana?

In a 1999 Pontiac Montana, the vacuum modulator is typically located on the transmission. Specifically, it can be found on the side of the transmission case, where it connects to the engine's vacuum source. To access it, you may need to lift the vehicle and remove any undercarriage components that obstruct your view. Always refer to the vehicle's service manual for precise location and replacement instructions.