The killer for a 2009 carbon filter is I have never found out how to remove it. I think the gas straps have to be loosened and the tank dropped a bit to get the filter out of its strap above the gas tank. I also think the line to the gas tank from the filter has to be removed at the sensor switch on top of the tank, accessible via a removable plate behind the passenger side back seat. But to do this and I am working from memory, it needs the sending switch removed to relieve tank pressure (requires another tool). Otherwise the sending switch assembly can rocket off. I have been fortunate that the carbon filter has maintained its integrity.
So anyone have the definitive word on how to remove the carbon filter from above the tank in a 2009 Sonata?