3. Scion iQ 1.3L (1,329 cc)
Scion‘s micro-subcompact can still somehow seat up to four, but that’s not its only impressive feature. By using a 1.3-liter (1,329cc) four-cylinder engine, which makes 94-hp and 89-lb-ft of torque, the peppy, yet frugal engine helps the iQ get a EPA rated 36/37 mpg. It’s not the smallest engine in the micro-subcompact market, but it is the most fuel efficient. That fuel-efficiency comes at a price though, and the Scion iQ costs a whopping $15,995, far more than its micro-subcompact rivals.