Splinter (2008)

While camping in the woods, Polly Watt and her clumsy boyfriend Seth Belzer damage their tent. They decide to spend the night in a low-budget motel. Meanwhile the criminals, Lacey Belisle and Dennis Farell, have trouble with their runaway car while heading to Platt and they walk on the lonely road. When Polly passes by Lacey, she stops the car and the couple is rendered by Dennis. However, Polly hits something in the road and while replacing the tire, they are attacked by a weird splinter. The car overheats and they stop in a gas station, where they are trapped by zombies, victims of the splinter parasite.