MacGyver is helping his old college buddy Jeff Stone develop and test an environmentally efficient car. However, Jeff has lost his ride with the Strickland racing team and MacGyver has convinced the Phoenix Foundation to provide Jeff with a new car. MacGyver is testing the car, which has a revolutionary plastic engine. At the test track, Carl Strickland and his top driver Hans Visser are watching and Strickland is worried that the car is too fast. Visser recognizes MacGyver from when he raced on the Formula One circuit. Meanwhile, Jeff and his daughter Charlie inspect the engine with the aid of their mechanic O'Malley. As Pete leaves to give the results to the board, Charlie talks of how she wants to be a driver. Jeff wants her to go to college first, and Charlie mentions her mother. Her comment clearly strikes a nerve and she makes a hasty exit. Jeff explains that once he wins the race and sells the car, he can settle down and not have to take her out on the circuit with him. He admits that his wife has settled down with a dentist because she wasn't worried that he might die during his job.
At the race reception, Pete, MacGyver, and Jeff spot Strickland giving a press statement. Strickland claims that Jeff's engine is a novelty, while Jeff notes that Strickland dumped him after Jeff refused to sell him his engine design. MacGyver spots Visser and remembers when he went off the track during a Formula One race. Visser shows off his victory ring from the race and assures the press that he will take the championship. He confronts MacGyver and Jeff and reminds MacGyver that he lost his nerve. Meanwhile, Strickland's investor Falco is worried that Strickland can't pull off the win, and wonders if they invested in the wrong car. Strickland warns Visser that he has to win and he has a secret weapon: O'Malley.
At the qualifiers, Pete discusses the system with Charlie and she asks why MacGyver quit racing. Pete admits that MacGyver never talks about it. Visser places first as O'Malley and MacGyver work on the car. When MacGyver is distracted, O'Malley sabotages the brake fluid gasket. As Jeff prepares to take to the track, Charlie gives him a lucky penny. Jeff takes to the track but the engine starts smoking and Jeff is forced to pull in. They discover the gasket has broken and they don't have a replacement. MacGyver makes an improvised replacement out of a pennant. O'Malley has no choice but to cut the brake lines. As Jeff drives away, Charlie discovers that her father dropped the lucky penny. Jeff's car goes out of control and slams into a tire wall.
At the hospital, Dr. Page tells MacGyver and the others that Jeff suffered flash burns. Charlie blames MacGyver for not properly fixing the brakes and storms off. MacGyver worries that he may have screwed up and isn't comforted by Pete's assurances. That night, MacGyver walks the track and remembers going off the track during the race against Visser. Meanwhile, Franco warns Strickland that if he doesn't win, he'll cut off his funding entirely. MacGyver talks to Charlie but she apologizes, admitting it wasn't his fault. MacGyver isn't so sure. Charlie talks about how her father explained how dangerous racing is but that you can't be afraid. She breaks into tears and MacGyver comforts her. After she goes to the hospital, Pete informs MacGyver that his seal was still intact and the right rear brake line was cut. They have no idea who performed the sabotage but MacGyver goes to the news satellite van and asks the man in charge, Moe, to show them the footage. MacGyver has Moe provide digital enhancement and they discover that O'Malley was responsible.
A drunken, guilty O'Malley goes to see Visser and Strickland at the hospitality tent. Strickland isn't impressed with O'Malley's lamentations and tells him to get the design specs for the engine. He warns that all it would take is one call to Interpol to get O'Malley arrested for a mistake he made 20 years ago. When O'Malley tries to go to the racing commission, Visser punches him and O'Malley falls facefirst unconscious into a decorative fountain. Strickland tells Visser to leave him.
The next day, Pete and MacGyver present the evidence of sabotage and ask for a delay. The official refuses to grant a delay but tells them he'll enter them at the back of the grid and they have 24 hours to get the car ready. MacGyver figures Strickland is involved and Pete goes to make a few calls.
At the hospital, MacGyver tells Jeff and Charlie about the situation. Jeff asks MacGyver to drive but he refuses. They call in another driver and Charlie takes MacGyver and Pete to an old car that Jeff has been using for parts. As they go to work, Pete does some checking and learns that O'Malley delivered a bomb for Irish terrorists 20 years ago and has been on the run ever since. He's also learned that Strickland's Japanese investors will want their money back if he loses. Later, Pete tries to track down O'Malley at the hospitality tent and spots a ring gem in the fountain.
As MacGyver works on the car, Pete gets a call and learns that the police have found O'Malley. He apparently drowned after his car went off the road but bruising indicates otherwise. They have the coroner draw a sample of water from O'Malley's lungs to determine if there is chlorine from the fountain there. Charlie arrives with news that the backup driver is stranded. MacGyver angrily refuses to drive and Pete finally gets him to explain that someone clipped him during a race and forced him into another driver, who died. Pete warns him that everyone is relying on him.
Visser is preparing for the race when he discovers the gem from his victory ring is missing. Strickland arrives as the announcer informs everyone that MacGyver will be driving. Visser is confident he can defeat MacGyver but Strickland tells him that he's rigged a fake fire extinguisher with nitrous oxide to give him an unbeatable edge.
As MacGyver prepares to drive, Charlie gives him Jeff's lucky penny. The drivers take their position and the race is on.
Pete and the medical examiner determines there's chlorine in the decorative fountain and that O'Malley's lungs had the same chlorinated water in them.
MacGyver jockeys for position and closes on the race leader, Visser. They're neck-and-neck on the last lap but MacGyver finally passes. Visser activates the nitrous oxide and passes, but goes off the track and MacGyver takes the lead again, crossing the finishing line and winning. Jeff listens from his hospital bed. As Pete cheers, he gets a message and goes with the police to arrest Strickland as he tries to slip away. Visser pulls into the pit and Pete has him arrested while revealing that the ring gem is the one from his victory ring. MacGyver pulls into the Phoenix pit and gives the checkered flag to Charlie, and tells her that next time she can drive.