What are some of the things? I know the air filter is clean. Tell me something else I can check. Just bought this one and just ordered the bently upon reading responses to others on this site. 'I thought the 18 was normal. One other thing. I was told the mpg computer works/I can hear the chimes go of but has no lights, can that be fixed of does the computer have to be replaced? Thanks for any help. I average 18 mpg going on short trips of about 10 miles. On the open road, I get a solid 28mpg on a flat road with the cruise control locked on 65 mph. I have tried this several times by setting the speed on the cruise control and resetting Avg MPG and runnig for 20 to 30 miles.