Max Verstappen's opening day at the Mexico City Grand Prix turned into a frustrating order, as persistent power unit issues rendered his Friday practice sessions "useless."
The Red Bull driver first reported a problem near the end of FP1, which forced him to sit out the final five minutes of the hour-long stint at the Autodromo Hermanos Rodriguez.
Although minor, the engine issue continued into FP2, during which drivers were primarily tasked with testing Pirelli's 2025 prototype tire compounds.
Over the radio, Verstappen reported a “weird noise” coming from his power unit, which he later described as “very disturbing.”
As a result, Red Bull called him into the garage, ending his session prematurely after just four lapses.
Reflecting on his curtailed day, Verstappen was visibly disappointed with how little he achieved.
"From the engine side we are checking, I don't know exactly what it is," the championship leader commented at the end of his day.
"But yeah, from my side [it was] a pretty much useless day. I did like four or five laps, and that's not much to read into.
"It'll be alright [without a penalty]. I never really had a good run. I did four or five laps in total and that's even with some long run laps in it. So a day to forget."
©RedBull
Red Bull's Helmut Marko confirmed that the team was facing a recurring issue that had previously been addressed.
While the exact cause of the problem remains unclear, Marko assured that it wasn't a serious problem and confirmed that no penalties linked to the unit's components were expected.
"It's the same problem, and we're in the process of finding out why it's come back, even though it's been fixed. It's not a serious problem, it just needs to be solved. There is a leak somewhere," Marko said.
"[We only did] two timed laps with Max [in FP1], and even those two timed laps weren't at full power. So it's going to be difficult, so thankfully this second practice session was on control tires and we weren't" "t allowed to change anything, so the damage is limited."
With Saturday's final practice session looming, Red Bull will aim to resolve Verstappen's power unit woes to put the Dutchman back on track for the remainder of the Mexico City Grand Prix weekend.
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