The Fuel-Efficient Scion xD 1.8-Liter Engine

 The 2010 Scion xD, the compact hatchback entry in Toyota's youth-oriented Scion line, has no engine changes for 2010. The xD's only engine is Toyota's 1.8-liter 2ZR-FE engine, which produces 128 horsepower and 125 lb-ft of torque.

Toyota introduced the 2ZR-FE engine in 2007, shortly before the debut of the xD model. Like the older 1.8-liter 1ZZ-FE engine it replaced, it is a 16-valve, DOHC inline four with an aluminum block and head. Toyota says the newer engine has much lower internal friction, for better fuel economy. It is shared by the xD, the Toyota Corolla, the Toyota Matrix, and the Pontiac Vibe, although the xD version has slightly less horsepower than the others.

 The 2ZR-FE engine is designed for low emissions and good mid-range response, rather than maximum horsepower. It is notably undersquare, with a bore of 80.5 mm and a stroke of 88.3 mm, improving low-end torque at the expense of high-speed power. It uses Toyota's Dual Variable Valve Timing with intelligence (Dual VVT-i) on both the intake and exhaust camshafts, varying the valve overlap (the amount of time the intake and exhaust valves are open simultaneously) for better drivability. The system also reduces catalytic converter warm-up time, improving cold-start emissions.
 Toyota's company website claims this engine has the highest fuel efficiency in its class. The 2010 xD's EPA fuel economy rating is 27/33 with either transmission, which compares well with the 1.5-liter Honda Fit, rated at 27/33 with manual shift and 28/35 with automatic. Despite its high 10.0:1 compression ratio, the 2ZR-FE engine does not require premium fuel.

Toyota Racing Development (TRD) offers two performance-oriented accessories for this engine: a Performance Air Filter (MSRP $80) and a Sport Muffler (MSRP $469). The TRD catalog claims the Sport Muffler improves horsepower, but it does not indicate how much.

Ronnie Tanner is a contributing writer at He writes about Scion xD Engine and other industry specific topics.