Q: I accidentally put premium gasoline in my car

Hi there. Premium will not harm your vehicle’s engine. In fact, premium is a required fuel for many of the luxury vehicles today to maintain performance and operation. Premium fuel has a longer burn time which results in fewer deposits left over from the burn; the regular grade has a fast burn time and is known to leave deposits from incomplete burns.

A longer burn time can aid in the prevention of a buildup in what is known in the automotive technology world as a "quench zone". As deposits build up in this zone they actually absorb fuel and additional deposits; if you’ve ever heard an older car continue to run after it’s been shut off this is what causes it to do that. If your car is designed to run on regular, then premium will not cause any problems. However, if your car requires premium, then regular can create drivability symptoms and a possible check engine light. I hope this information helps you.