What is a Fuel Composition Sensor?
Is it for late model EFI vehicles that can use different ratio of alcohol content from today's gas pumps?
I'll have to dig out my alcohol fuel hydrometer and check the specific gravity of some of my pump E 85 left over from last year and check the E98 I still have sealed up in the bottles I bought from Wal Mart last year work

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)