Slammin' Sammy's Stunt Show Spectacular - S1-E5
Deliberate mistake: Watch the end of the test run for Michael and KITT. Michael was using the KITT steering wheel, but then he gets out of the car and it switches to a performance steering wheel instead.
Knight Rider [Pilot; a.k.a. Knight of the Phoenix] (1) - S1-E1
Deliberate mistake: Watch the scene when Michael fell asleep. At the end of the cop chase the cops get out. Watch the license plate California KNIGHT in yellow letters. The next scene reads Nevada MCC224 and has an original Trans Am rather than KITT's rear.
Answer: KITT didn't choose to go off the cliff in Goliath Returns, it just happened as he tried to avoid Goliath. Just 'cus it happened, doesn't mean It's gonna cure his fear of "flying"