Stellantis faced assembly disruptions on certain Fiat models in Italy in October because of N3 GSE engine electronic control unit (ECU) shortages, with effects expected to persist.
The component bottleneck constrained vehicle availability, volumes and market share, resulting in the carmaker's first monthly decline of the year in Italy's auto market.
According to the press statement, production of the Fiat Pandina was hit hardest.
Disruption is expected to continue through November and December, potentially affecting the Pomigliano d'Arco plant, which builds the Pandina, and the Mirafiori site, where the Fiat 500 is made.
Stellantis said it was working with suppliers to restore full production availability.
It added that, despite October's drop, it retained market leadership in Italy for the month and on a year-to-date basis.
Separately, Leapmotor International, a joint venture between Stellantis and China's Leapmotor Technology, said last month it planned to build the Leapmotor B05 at Stellantis' Zaragoza plant in Spain.
B10 assembly has already started at the site, making the B05 the second Leapmotor model slated for production there.
Leapmotor delivered 106,127 vehicles worldwide in October, up 51% from about 70,300 units in October 2025.
In July, Stellantis entered the US micromobility segment with the launch of the Fiat Topolino.
The low-speed electric vehicle is aimed at lifestyle and neighbourhood settings such as private residential developments, resorts and coastal towns, and shares major components with the Citroën Ami.
In its latest financial update, Stellantis kept its full-year guidance despite posting another substantial quarterly loss and a large cash outflow.
Third quarter net revenues were €37.6bn ($42.11bn), up 1% from Q3 2025. The net loss was €0.5bn, against €4.5bn in the year-earlier quarter.
Regarding other market activity, Stellantis announced last month that it will invest approximately Rs40bn ($421.5m) in India over a three-year timeframe, intending to release 12 products, increase localisation, and treble annual sales volume to roughly 45,000 units.
