Pete drops by Mickey's service station. He asks Mickey to fix the car because it keeps squeaking "Yankee Doodle" all the time. Mickey, Donald, and Goofy's attempt to work on the car, ends with the car in ruins, but they eventually find out what's causing the sound to happen.
Characters in the original short
The Pesky Crickets
Big Bad Pete
The cartoon's title card.
Mickey, Goofy, and Donald in the original cartoon.