Perhaps his most prominent role has been as the quarterback Derek McConnell in ESPN's short-lived series Playmakers. Wiehl has made guest appearances on television shows including Popular, CSI: Crime Scene Investigation, Birds of Prey and Charmed (for the episode Animal Pragmatism). He had a spotlight role in the 2000 film Broken Hearts Club as J.Crew Guy. He also played a small role in the movie Can't Hardly Wait.
Wiehl was a guest star on Buffy the Vampire Slayer during season one, in the role of "Owen" in the episode "Never Kill a Boy on the First Date". He also played a police officer in Hollywood Homicide in 2003 as "Cheeseburger Cop".
In 2006, he played Jake Dunne on Love Monkey. He had a recurring role as Roger on Jericho. He plays art gallery owner Patrick on Switched at Birth.