Police say the victim had a blowout on South Post Oak at South Main around 2:45am Sunday.
He was changing the tire when a van hit him.
Police said the driver of the van stopped and told two female passengers in the car to call 9-1-1, and then he fled.
The victim died at the scene.
While police were investigating the fatal accident, a white pickup struck an officer's patrol car and kept going.
Police caught up to that driver at South Main and Beltway 8. He was arrested.
Anyone with information about the van or its driver is urged to call Crime Stoppers at 713-222-TIPS.