all-new Audi 100 in 1992, Audi introduced a 2.8L V6 engine. This engine was also fitted to a face-lifted Audi 80 (all 80 and 90 models were now badged 80 except for the USA), giving this model a choice of four-, five-, and six-cylinder engines, in saloon, coupé and convertible body styles. The five-cylinder was soon dropped as a major engine choice; however, a turbocharged version remained. The engine, initially fitted to the 200 quattro 20V of 1991, was a derivative of the engine fitted to the Sport Quattro. It was fitted to the Audi Coupé, named the S2, and also to the Audi 100 body, and named the S4. These two models were the beginning of the mass-produced S series of performance cars. Audi 5000 unintended acceleration allegations Sales in the United States fell after a series of recalls from 1982 to 1987 of Audi 5000 models associated with reported incidents of sudden unintended acceleration linked to six deaths and 700 accidents. At the time, NHTSA was investigating 50 car models from 20 manufacturers for sudden surges of power. A 60 Minutes report aired 23 November 1986, featuring interviews with six people who had sued Audi after reporting unintended acceleration, showing an Audi 5000 ostensibly suffering a problem when the brake pedal was pushed. Subsequent investigation revealed that 60 Minutes had engineered the failure – fitting a canister of compressed air on the passenger-side floor, linked via a hose to a hole drilled into the transmission. Audi contended, prior to findings by outside investigators, that the problems were caused by driver error, specifically pedal misapplication. Subsequently, the National Highway Traffic Safety Administration (NHTSA) concluded that the majority of unintended acceleration cases, including all the ones that prompted the 60 Minutes report, were caused by driver error such as confusion of pedals. CBS did not acknowledge the test results of involved government agencies, but did acknowledge the similar results of another study. In a review study published in 2012, NHTSA summarized its past findings about the Audi unintended acceleration problems: "Once an unintended acceleration had begun, in the Audi 5000, due to a failure in the idle-stabilizer system (producing an initial acceleration of 0.3g), pedal misapplication resulting from panic, confusion, or unfamiliarity with the Audi 5000 contributed to the severity of the incident." This summary is consistent with the conclusions of NHTSA's most technical analysis at the time: "Audi idle-stabilization