Q: if my transmission fluid was filled a quart over could this cause my reduced engine power light to come on?

Hi there. Usually the reduced power light is caused by an engine component failure, like the throttle body, TPS or bad O2 sensors. It is very possible that the additional transmission fluid has created a trouble code that might have activated a Limp Mode setting for your Chevy. When the internal engine or transmission sensors determine a fault exists inside the transmission (which can be triggered by too much hydraulic pressure due to excessive fluid), it tends to create a limp mode, so you can slowly drive the vehicle to a repair facility. Two things can be done to resolve this issue. First, flush the transmission fluid and change the filter first. Second, a professional mechanic will need to complete a reduced engine power light inspection to deactivate the limp mode; which should resolve this problem. If that doesn’t work, a detailed inspection might be warranted.