Buick Regal engine power is reduced, restarted and returned to normal.

The steps of reducing power, restarting and returning to normal of Buick Regal engine are as follows:

1. Press the accelerator pedal to the bottom and check whether the throttle valve can be fully opened.

2. Check whether the exhaust system is blocked.

3. Check whether the air intake system is blocked or leaked.

4, check whether the fuel system oil supply is normal.