It's not exactly a setup that is optimized for fuel economy. However, I manage to squeeze mpg (yes, decimals count when it's this bad) out of it on average.
Use unleaded regular gasoline with an octane rating of at least 87 AKI (Anti-Knock Index) number (Research octane number 91). CAUTION. There is a big difference in E85, 10% Ethanol and pure gasoline. Detailed specs and features for the Used Nissan Altima including dimensions, horsepower, engine, capacity, fuel economy, transmission, engine type.