If the check engine and reduced engine power lights are on, the throttle may be disabled and a noticeable reduction in the vehicle's performance may occur.
If the reduced engine power light is on, but there is no reduction in performance, proceed to your destination. The performance may be reduced the next time the vehicle is driven. The vehicle may be driven at a reduced speed while the reduced engine power light is on, but acceleration and speed may be reduced.
Anytime the check engine light stays on, the vehicle should be taken to an authorized GM dealer as soon as possible for service.