Every 2006 Honda Civic Sedan gets the same engine, a 1.8-liter, inline four-cylinder equipped with i-VTEC variable valve timing. With 140 horsepower available at 6,300 rpm and 128 lb.-ft. of torque peaking at 4,300 rpm, the 2006 Civic Sedan’s engine is more powerful than both motors offered in 2005 and runs on regular unleaded fuel. A five-speed manual transmission sends the power to the front wheels, and is estimated to provide 30 mpg in the city and 38 mpg on the highway. The optional five-speed automatic is expected to do even better when it comes to fuel efficiency, matching the manual’s city rating but getting 40 mpg on the highway.