Christian Horner says that a problem with a sensor on one of Sergio Perez's cylinders almost caused the Mexican to retire from the Miami Grand Prix.
Perez's issue in the first half of Sunday's race was estimated to have cost him 20 kilowatts of power, and meant that he was not able to overhaul Carlos Sainz for third, even with a fresh set of Soft tyres towards the end of the event.
"[Perez] had an issue with a sensor on one of the cylinders, so he lost a lot of track time," Horner told media, including RacingNews365.com.
"The guys managed to move the sensors around, but he was down probably 20 kilowatts in power as a result.
"Even with the advantage of the new tyre he had, he was probably half a second off what the car was capable of in straight-line speed, and I think without that he would have probably even been P2."
Asked how close Perez was to retirement, Horner replied: "Very close. We managed to move the sensors around and managed to address the issues, so it's something we'll work closely with HRC (Honda Racing Corporation) on to try and understand, and obviously ensure that it doesn't happen in the future."
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Horner unconcerned about questionable reliability
Though the Red Bull RB18 has proved fast, with Max Verstappen taking three wins so far this season, reliability has so far been an issue.
Both cars retired from the closing stages of the Bahrain Grand Prix, while Verstappen also failed to finish in Melbourne and had his Friday running curtailed at Miami.
But despite Red Bull's litany of retirements so far in 2022, Horner denied that the RB18 was less dependable than the team would like.
"It's not particularly fragile," Horner said of the car.
"I think there's just been niggly things that you would have normally seen in pre-season testing that have only reared their head as we've got into the season, so that's been frustrating.
"But we're working closely with [Honda] and they're giving us great support, so I think we'll get those ironed out."
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