2011 Patriot Sport reduced gas mileage
I have a 2011 Patriot Sport 2.4L, FWD,CVT
purchased new, drive about 325 miles a week , 250 of them highway.
I was enjoying a constant 27 mpg like clockwork(no computer calculation) just logging gallons, & miles.
Last June 2015, it was like someone turned a switch I dropped down to about 25 mpg, & progressively, worse, to now at 22.25 mpg.
I am a 57 year old male observe speed limits, try to drive in a manor that would promote good fuel economy.
I have always followed general maintenance recommendations , have ran a K&N air filter since new, washed & re-oiled on schedule , changed spark plugs as due in manual using exact oem part, cabin filter as scheduled, fuel system cleaning at the scheduled interval, recently installed original paper filter and replaced air intake temp sensor thinking I may have developed oil film on the sensor from the K&N filter.
I have also had dealer service the CVT fluid & filters 2 weeks ago at 85,000 miles.
Last summer I had them make an attempt to diagnose poor economy , I was told that every test was in speck, & that if I was getting 27 mpg I had the best Patriot ever built.
I have found the dealership in Massillon Ohio to be smug, condescending, and less than helpful.
The acceleration is somewhat hesitant.
I am now past my extended warranty, & am hoping to drive this vehicle for at least another year.
I am considering o2 sensors next, given the long history mentioned in this first post, I am seeking opinions from the experienced membership here.
Thank you in advance