Honda admits it underestimated Mexico cooling demands after Aston Martin double retirement

Honda has accepted responsibility for Aston Martin’s two retirements at the Mexico City Grand Prix. Shintaro Orihara, Honda’s trackside general manager and chief engineer, says the manufacturer underestimated the cooling demands of the high-altitude circuit.

Fernando Alonso and Lance Stroll both retired on lap five of 71. Power-unit trouble had already limited Alonso to 17th on the grid in qualifying; Stroll was affected by the same issue.

At the Autódromo Hermanos Rodríguez, nearly 2,250 metres above sea level, thinner air reduces cooling efficiency and makes turbochargers work harder. Orihara said Honda had expected extra cooling challenges, but the ERS cooling circuit came under more stress than anticipated.

Orihara said the fault had shown no warning signs in earlier running. Despite a series of practice laps, it appeared in qualifying and again in the race.

The trouble came during an already difficult 2026 for Aston Martin’s partnership with Honda: severe vibration issues damaged battery packs and curtailed pre-season running, while Honda’s engine lagged behind rival manufacturers in straight-line power.

Looking to 2027, Orihara said Honda would use the setback in work on its redesigned power unit. He said the manufacturer had data, including on turbo lag, to take back to the circuit next year as it works on solutions.