Wahi started his acting career with the 2004 "Rose Audio Visuals" television series Remix, where he portrayed the lead role of Ranveer Sisodia, a angry lover boy character, opposite Shweta Gulati. The story of the show is based on the lives of 12th-grade students in an elite school for the kids of the rich and the famous, and scholarship students from poorer families. His performance in the show won him Indian Telly Award for GR8 Best Male Newcomer.
After a long break from fiction shows, Wahi make a comeback in fiction opposite Mugdha Chaphekar to play the lead role of Rajveer in the 2009 Colors TV's soap opera Mere Ghar Aayi Ek Nanhi Pari. The story revolves around a family of Delhi who experience the birth of a daughter after long 18 years.[
Karan also portrayed alongside an ensemble cast including Sehban Azim, Shilpa Anand, Moulshree Sachdeva, Neha Jhulka in the popular show DILL MILL GAYYE.
He was seen with Barun Sobti in the popular dram show Baat Hamari P