Q: Can I damage my Toyota Yaris by using premium gas? I have a 2010 Toyota Yaris sedan. I just filled up my tank with super unleaded, but somebody told me it's not good to put super unleaded in a car rated for regular.
A: The only damage that resulted from putting premium gas in your Yaris was to your wallet, and hopefully you won't make that mistake again.
Pumping higher-octane premium gas into a car designed to run on regular does not provide a significant improvement in performance or fuel economy, but it won't damage your engine, either. It's like paying more for a name-brand product when the lower-priced generic equivalent is just as good.
On the flip side, using regular gas in a car designed to run on premium can result in a loss of economy and performance and perhaps engine "pinging" or knocking during acceleration.