I would say buy a cheap Ford code checker at a parts shop just on priciple. As for more power in the cooler wet conditions, that is normal. Cooler air is more dense than warm air. More atoms in a smaller space. that's why if you leave a basketball outside when it's cold, it goes soft as if underinflated, and why it hardens back up as it warms up.
Wet air is also a factor, although I cannot remember why from science class. Damn brain, killing my beer cells...I mean beer killing brain cells...;D
