Engine Power Reduced Cadillac Cts. It would not go over 20 mph. “reduced engine power” or “engine power is reduced⁠” is a warning message that continues to baffle and frustrate many general motors (gm) vehicle owners.

I pulled over, shut it off, restarted it, and it was fine for another 10 min when it did this. All of a sudden, engine would not rev and reduced engine power flashed on the screen. Took it to dealer they wanted 100 dollars per code.