The Geo Storm was a rebadged version of the sporty Isuzu Impulse minus some of that car's more expensive features. The Storm and the Impulse were sold in Japan as the PA-Nero and related Gemini Coupe. The Storm lacked the Impulse's Lotus-tuned suspension as well as the Impulse's optional turbocharger and all-wheel drive drivetrain. Although they were essentially the same car, sales of the Storm were much stronger than those of the Impulse—indeed, the Storm sold better than most small GM cars of that era. Slow sales of the Isuzu version doomed the Storm as when the Isuzu Impulse was canceled, the Geo Storm derivative had nothing to be built from, meaning both cars were discontinued in 1993.
The Storm was manufactured at Isuzu's main plant in Fujisawa, Kanagawa, Japan. The Storm and Impulse was sold in Canada by GM as the Asüna Sunfire.
The most common body style for the Storm was a three-door hatchback. The 1990 and 1991 hatchbacks were produced in two trim packages, but all Storms shared front disk and rear drum brakes and had an anti-sway bar to tighten the front suspension. The base model was priced at $10,390, and the GSi was $11,650.USD
The base model's SOHC engine produced 95hp (71kW) and had a 9.1:1 compression ratio. The more powerful 1990-1991 GSi used a 1.6L DOHC engine that produced 130hp (97kW) and had a 9.8:1 compression ratio.. The GSi package also included driving lights, a spoiler, a rear anti-sway bar, and a transmission with a gear ratio that was slightly better for acceleration than the base model's transmission.
For 1991 and 1992, customers had the option of purchasing a two-door station wagon body style, also called a wagonback. The base price of the station wagon was $11,450, and it was never offered with the stronger GSi engine. Oddly, the station wagon was marketed as a "hatchback" and the normal Storm - an actual hatchback - was marketed as a "coupé".
In 1992, the Storm was restyled to have a smoother front fascia without the pop-up headlight covers on earlier models. The 1992–93 base models retained the same engine, features, and price that were on the earlier car, with slight interior changes such as different stereos, revised rear speaker locations, and interior trim and upholstery. The GSi version from these years cost considerably more ($13,645–14,560) but this price included a larger 1.8L 140hp (104kW) engine.