MacGyver is working with his old college friend, race car driver Jeff Stone, to develop an environmentally efficient car. Jeff's former sponsor, the Strickland Company, has fired him so MacGyver has set Jeff up with the Phoenix Foundation as his new sponsor. MacGyver is driving Jeff's car with its new experimental plastic engine on the test track. Watching from a distance is Carl Strickland and his driver, Hans Visser. Strickland is concerned that Jeff's car is faster than Visser's. Using binoculars, Visser recognizes MacGyver from when they've crossed paths on the Formula One circuit in Europe.
MacGyver comes in just under the track record and pulls up to Jeff and his daughter Charlie. They go over the car with the aid of their mechanic, O'Malley. Pete goes to report to the Foundation's board that the plastic engine is performing up to expectations. As Jeff and Charlie inspect the car, Charlie talks about how she plans to become a race car driver. Jeff reminds her that she'll go to college first and Charlie mentions her mother, Meg. Once Charlie leaves, Jeff admits to MacGyver that he wants to settle down once he finishes development of the engine, and that he's never wanted to haul Charlie out on the road with him. MacGyver asks when the last time Jeff saw Meg and Jeff admits that his ex-wife has remarried a dentist, someone who she could count on coming home to.
MacGyver, Jeff, and Pete attend the race reception at the hospitality tent. Strickland is giving a press statement on his new engine and boasts that it's superior to Jeff's plastic engine, which he describes as a "novelty." Jeff complains that Strickland wanted to buy the design from him originally, and fired Jeff when he refused. MacGyver spots Visser talking with a reporter and remembers how he went off the track in a Formula 1 race. Visser is showing off his Formula 1 victory ring and boasting that he'll take the championship here as well. He then talks with MacGyver and suggests that he's lost his nerve.
Strickland slips away to talk to his overseas backer, Falco. Falco is concerned that Strickland can't win the championship. If Visser loses, then Falco's people will withdraw their funding. Strickland goes to tell Visser that it all depends on him but that they have a secret weapon: O'Malley.
At the qualifiers, Charlie explains to Pete how the starting lineup works and asks why MacGyver quit race car driving. Pete tells her that MacGyver has never told him either. Visser places first in the time trials. O'Malley manages to sabotage the brake fluid gasket before Jeff takes to the track. As Jeff prepares to leave, Charlie gives her father the lucky penny that he's worn in all his races. Jeff makes the first lap but his engine starts smoking and he's forced to enter the pit. They discover the gasket has broken and O'Malley says they don't have a spare. MacGyver makes a crude gasket out of a pennant and O'Malley secretly cuts the brake line. Jeff drives away, dropping his lucky penny. As Charlie picks it up, Jeff's car spins out of control and slams into a tire wall.
At the hospital, Jeff's doctor informs MacGyver, Pete, and Charlie that Jeff suffered only minor injuries in the crash, but was blinded by flash burns. Charlie turns against MacGyver, saying it's his fault the brake lines didn't work. She runs off and MacGyver is forced to wonder if he's right. He goes back to the track and remembers the past, including his last race against Visser. He goes to see Charlie who apologizes for overreacting. Pete arrives and tells MacGyver that the Foundation team has determined that the cause of the crash was a sabotaged brake line. They figure someone in the pit committed the sabotage and go to the central news van. The operator, Moe, is initially reluctant to help but MacGyver gives him a few tips on digital enhancement and they soon learn that O'Malley is responsible.
O'Malley meets Strickland and Visser at the hospitality tent. The mechanic is drinking heavily out of guilt. Strickland has been blackmailing O'Malley into undermining Jeff and wants him to steal the design specs for the plastic engine. He warns the mechanic that if he doesn't cooperate, he'll call Interpol. O'Malley refuses to cooperate and leaves to warn the racing commission. Visser punches him, knocking him into a decorative water fountain. When O'Malley fails to get out, Strickland tells Visser they have the perfect means to get rid of him.
The next day, MacGyver and Pete go to the racing commission and ask for a delay because of the sabotage. The official in charge warns that they can only delay the race 24 hours due to the contracted network coverage. Because of the special circumstances he allows them to enter in last place. O'Malley is missing and MacGyver figures that Strickland is somehow involved.
MacGyver goes to the hospital and tells Jeff and Charlie what's going on. Jeff insists they need MacGyver to drive the car but he refuses. They call another driver to fly in and drive. While he's on the way, Charlie shows MacGyver an old car that they can use with the plastic engine. Pete checks O'Malley's history and learns he worked with Irish terrorists 20 years ago and has been on the run ever since. He also learns that Strickland's investors will withdraw their funds if Visser loses the race. As Pete searches for O'Malley, he checks out the hospitality tent and spots a small green gem in the water fountain.
The police find O'Malley, dead. It appears that his car went off the road into the ocean while he was drinking. However, bruising indicates that he drowned before the impact occurred. MacGyver gives Pete some antibiotic that can be used to test for the presence of chlorine. They're interrupted when Charlie arrives with news that their backup driver is unable to fly in due to bad weather. MacGyver still refuses to drive and Pete demands an answer. MacGyver explains that during his last Formula One race, Visser clipped him and when MacGyver went out of control, he crashed into another car and killed the driver. Pete suggests that he get over it and if he doesn't, a lot of people will be disappointed.
Visser is suiting up for the race and notices that the gem from his Formula One victory ring is missing. He spots MacGyver taking Jeff's place in the race and meets with Strickland. The CEO informs his driver that he's installed a hidden canister of nitrous oxide in the Strickland car to give him the necessary edge to win. Meanwhile, Charlie gives MacGyver Jeff's lucky penny and wishes him good luck.
As the race begins, Pete and the medical examiner, Simms, check the water in the fountain and discover it has the same chlorine levels as the water in O'Malley's lungs.
Thanks to his driving skills and the plastic engine, MacGyver moves up from last place and finally catches up to Visser. Visser uses the nitrous oxide but goes off the track and MacGyver passes him. By the time he catches up, it's too late: MacGyver wins the race as Jeff listens from his hospital bed. Pete and the police arrest Strickland and Visser, showing them the victory ring gem that places Visser at the crime scene. MacGyver gives the checkered victory flag to Charlie and assures that the next time, she'll be the one doing the driving.