Busch posted the fastest average speed of 130.813 mph early in the 50-minute session Friday at Phoenix Raceway but ran eventually ran into an issue.
Just over 32 minutes into the session, A.J. Allmendinger drifted up the track and into Busch in Turn 4 and the two made contact. Allmendinger spun around which brought out a caution.
The damage did not appear extensive to either car. The session resumed several minutes later.
Larson was the slowest of the Championship 4 drivers, ending up 11th fastest.
Among those drivers who ran at least 10 consecutive laps, Bell had the fastest average lap speed (129.600 mph). He was followed by Blaney, Byron, Kevin Harvick and Busch in that category.