Are you putting gas into the car periodically? I ask because you didn't mention Fuel Maintenance Mode, which occurs when the gas reaches an average of ~360-365 days old.

 

Thank you for your quick reply. In three and a half years I think I've only put gas in about ten times, even then the fuel gauge was only half empty. What is the "Fuel Maintenance Mode"? I'm just concerned about whether not running on the gas mode could cause the gas to go stale and damage the system.

 

not running on the gas mode could cause the gas to go stale and damage the system.

The car was designed with this in mind. It will force the engine on to burn gas if needed. The fuel tank is sealed and pressurized to minimize the speed at which the fuel gets stale.

-Charlie

 

research FMM here and you will find all the answers... As obermd indicated, the car monitors the average age of the fuel and will initiate a FMM when the average age of the fuel hits 365 days old. You must have added just enough at the right times to avoid it thus far.

Yes stale gas is an issue. There are strategies to minimize the age by running it nearly out, and then just adding 3 or so gallons to minimize the amount that needs burned off when it gets old.

 

Thank you for all of the helpful responses, especially for pointing out the FMM, which I never was aware of.