Subaru’s Octane Coverup: How a Major Automaker Failed to Fix a Systemic Engine Problem

In 2019, I purchased a Subaru Impreza advertised as taking 87-octane gasoline. The owner’s manual explicitly stated that 87-octane fuel should be used. Yet within months of ownership I had noticed that during low-RPM acceleration events the engine sometimes produced an unmistakable pinging sound: like the metallic rattling of a shopping cart rolling over rough …