2008 Honda Civic Fuel System Other Problems

'08 HONDA CIVIC HYBRID EXPERIENCING A DRAMATIC DECREASE IN FUEL ECONOMY. IMA BATTERY SUSPECTED. DEALERSHIP UPGRADED SOFTWARE (AS PER HONDA RECALL) AND TOLD ME THAT TO GET BETTER MPG'S I SHOULD SHUT OFF MY HEATER (WE LIVE IN WISCONSIN!) AND RECOMMENDED AN AIR FILTER CHANGE. I STATED THAT AN AIR FILTER AND SHUTTING OFF THE HEAT WOULD NOT INCREASE MY MPG'S FROM 28-31 BACK UP TO IT'S PRIOR PERFORMANCE RANGE OF 40-50. VEHICLE IS STILL DRAMATICALLY UNDERPERFORMING. NOTE: SERVICE ADVISOR @ BERGSTROM HONDA ADMITTED THAT IN HIS 4 YEARS THERE THAT HE HAS SEEN MANY CIVIC HYBRIDS WITH SEVERE TIRE CUPPING (I PREVIOUSLY FILED COMPLAINTS ON THIS ISSUE ALSO, VEHICLE IS GOING ON IT'S 3RD SET OF TIRES WITHIN 57,927 MILES!) AND ALSO MENTIONED THE POOR PERFORMANCE AFTER THE HONDA SOFTWARE UPGRADES TO FIX THE IMA ISSUES. IT IS MY BELIEF THAT HONDA IS WELL AWARE OF THE IMA ISSUES AND IS TRYING TO HIDE THEM UNDER THE SOFTWARE UPDATE (TO SAVE REPLACING "X" NUMBER OF EXPENSIVE HYBRID BATTERY'S). I BELIEVE THAT AS OWNERS WE HAVE LOST VALUABLE LIFESPAN ON THESE BATTERY'S AND THAT WE HAVE LOST OUT ON A GOOD PORTION OF OUR HYBRID BATTERY WARRANTY COVERAGE DUE TO HONDA'S DESIGN. *TR