The Gen 1 Prius was the world’s first mass-produced gasoline-electric hybrid car. It was an industry game-changer, available for less than $20,000 in the U.S., which enabled hybrid vehicles to gain market traction amongst consumers. Power was supplied by its 1.5L 4—cylinder gasoline engine delivered 70-hp and 82 ft.-lb. of torque, in conjunction with a 274V nickel-metal hydride (Ni-MH) battery pack that generated 44-hp (33 kW) and 258 ft.-lb. of torque. It offered outstanding fuel mileage of 41-mpg combined (42 city and 41 highway). Qualified technicians with the proper tools, service information and ongoing training can readily service the Gen 1 Prius, but verify rather than assume. (Refer tips here.) With 5 million plus Toyota battery packs in use today, their reliability has been good, with the exception of the Gen 1 Prius, notably in regards to worn battery cells and corroded connections. Total battery pack replacement is expensive, and few technicians have the expertise and equipment to repair and balance smaller battery pack components, such as faulty modules or individual cells. Even with a major recall for Gen 1 battery packs, it has continued to be problematic. Were I looking to purchase a Prius today, I’d avoid the Gen 1 and opt for a newer and more dependable generation.