The primary risk of driving a Volkswagen car with a Balancer Shaft problem is that it can cause severe engine damage. This is because the balancer shaft is an important component of the engine that helps maintain balance and reduces vibration. If the balancer shaft is damaged or malfunctioning, the entire engine can become out of balance, which can cause excessive vibration and strain on components. This can lead to component failure, leading to costly repairs or even engine replacement.