Wheely Applegate can occasionally be seen as egotistical, can be silly due to his overworked and anxious sides (and the fact he is played by Don Knotts). He did lie to Herbie at one point saying Giselle didn't really love him but it was so he could focus on their plan of winning the race.
Despite his supposed egotistical and sort of selfish sides, he is a loyal friend to Jim and Herbie and a smart and helpful mechanic. He really is happy for Herbie when he finds him on a date with another car, he just doesn't want him to be so lovestruck for her when they are trying to win the race. Wheely does also apologize for his errors near the end and does end up dating the trophy girl.
Wheely is friends with Jim Douglas. He is a mechanic attempting to resuscitate Jim's racing career with a race in Europe.