Yes, colder air = slightly more hp's (hard to say exactly how many more hp's , but our engine only produces 109 hp as it is.

Actually, on the scangauge 2, its a known fact that in the summer time where I live my air intake temp. (which the scangauge 2 produces a minute-to-minute read out of exact engine temp. degree F, reading) tends to be 100 to 130 degrees F , which also results in higher MPG's. In late Fall/ winter, my air intake temp. is usually 55-75 degrees, and I notice a decreased mpg overall (dividing # of gallons of gas, but total # of miles driven).