For 1998, Minardi signed Shinji Nakano from Prost Grand Prix and Argentine rookie Esteban Tuero. The M198 was powered by a Ford Cosworth V10, a significant step up in configuration if not always in results. Tuero conducted early testing of the new engine in January at Mugello; Nakano joined the programme in Barcelona in February.
Tuero's participation was briefly in doubt as his FIA super licence had not yet been granted at the start of preparations. He was eventually awarded the licence and, at 19 years old, became the third-youngest Formula One driver at the time of his debut.
At the season opener in Australia, Tuero qualified 17th — ahead of 1996 Monaco Grand Prix winner Olivier Panis and both Tyrrell entries — but both M198s retired from the race. A double retirement was repeated in Brazil. Nakano brought the car to its first finish in Argentina.
Reliability was the car's defining weakness throughout the year. The M198 failed to finish 18 times across the season. Tuero completed just four of his entered races, a retirement rate of 75%. Nakano suffered six retirements, meaning three Grands Prix where neither M198 reached the chequered flag. Combined, this left Minardi well short of points, though they did finish ahead of Tyrrell in the final Constructors' standings — a distinction achieved without either team scoring.
The season's competitive high point came at the Canadian Grand Prix, where Nakano finished seventh. At the final race in Japan, Tuero was involved in a collision with Tora Takagi that caused lesions across three of his spinal vertebrae. Debris from the incident reached Michael Schumacher's Ferrari, forcing it to retire; Mika Hakkinen went on to clinch the drivers' title in that race.
The M198 carried a notable visual change from the M197, adopting a silver and blue paintjob in place of the previous black, yellow, and white scheme. Sponsors included Fondmetal, Roces, Avex Group, and Doimo.
Following the season, Minardi used the M198 for a winter test at Barcelona in December 1998, with Laurent Redon, Marc Gene, and Italian Formula Three champion Donny Crevels all driving. Gene impressed sufficiently to secure a race seat for 1999, going on to drive the successor M01 — which adopted a new naming convention marking the end of the M1xx era.
The M198 closed out a naming lineage that had run from the M185 through to the M198, spanning fourteen years of Minardi's Formula One history. The car's switch to Cosworth V10 power reflected the team's attempt to keep pace with the field, but mechanical fragility undermined any potential gains. Tuero's injury in Japan, and the close call involving Schumacher, underlined the physical risks that accompanied racing at the back of the grid in an era before the safety improvements of the following decade.