It's in the cap for the air filter box. Notice that little wire that pokes out the top of it? In the manual it's referred to as an intake air temp sensor, but I believe it does the same job as a MAF airflow sensor, using a heated wire and more air -> cooler wire -> more electricity needed to heat wire so it knows roughly how much air is entering the engine that way. I can't find any other sensor in the intake system.
