Honda admits Aston Martin AMR26 worsens engine vibration issues

Honda’s Koji Watanabe has revealed that the vibrations afflicting its F1 2026 power unit are far worse when fitted into the Aston Martin AMR26 than on the dyno.

Honda’s power unit has been afflicted by constant vibration issues that have forced it and Aston Martin to concentrate on developing countermeasures to establish a stable baseline of reliability.

Koji Watanabe explains Aston Martin AMR26 vibration problem

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Ever since the AMR26 first took to the track in Barcelona in January, the Aston Martin team has struggled for reliability that would allow Lawrence Stroll’s squad to start racking up serious mileage and concentrate on developing performance.

With Aston Martin the only team running the Honda power unit, the lack of mileage in pre-season testing exacerbated the lack of learning compared to the likes of Mercedes High Performance Powertrains [HPP], which powers four teams, and Ferrari, which powers three teams.

Vibrations through the power unit resulted in serious battery pack issues during pre-season testing, with Honda having to curtail running in the final days in Bahrain as the full extent of the problems became apparent and stocks of batteries ran low.

Things have marginally improved since: while vibrations continue to plague the Honda power unit, Fernando Alonso managed to finish the Japanese Grand Prix in 18th place – the team’s first finish of the season after double retirements in Australia and China.

But with such milestones being well in the rear-view mirror for all the other teams and power unit manufacturers, it’s clear that Honda and Aston Martin are in for a very difficult year, although there is a sense that there is some optimism the AMR26 could prove somewhat competitive once reliability is found; team boss and managing technical partner Adrian Newey believes the chassis could rank in the top five on the grid.

Honda’s Koji Watanabe appeared before the media in Japan and was asked what success looks like for the Japanese manufacturer after such a difficult start to 2026.

“Well, we have some recovery plan together with Aston Martin, but we cannot tell that today,” was his succinct reply.

It’s a huge change in the level of expectation of Honda, who were at the forefront of the sport over the last half-decade through the extended engine freeze between 2022 and ’25.

Winning a title with Max Verstappen in 2021, coinciding with its official withdrawal from the sport, an agreement with Red Bull saw Honda continue to manufacture and maintain power units for the two Red Bull squads, although there was no additional development through these four years.

Winning titles in every season apart from 2025, Watanabe was asked why the experienced manufacturer had not encountered any such issues working with Red Bull.

“We have enough experience until 2025. As I told you, the most difficult point is that we started the development a bit later compared to the others,” he said.

“Also, in the test on the dyno, the vibration is at an acceptable level, but once we integrate in the actual chassis, that vibration is getting much more than the test on the dyno.

“So, of course, on the PU (sic) we cannot solve the problem, only the PU, so we are really closely together with Aston Martin Aramco to solve the problem, not only the power unit, but also together with the chassis.”

Watanabe’s answer hints further at the validity of pre-season claims from Honda that Newey had requested late changes to the way the power unit integrated into the chassis, following his own arrival at the Silverstone factory in May 2025.

All the efforts since pre-season testing have been on finding ways to introduce countermeasures to dampen the vibrations, which reached a good point at Suzuka as Fernando Alonso revealed he had not encountered any such issues during practice on Friday, only for vibrations to return on Saturday despite no changes having been made.

With Honda seemingly almost certain to be granted more development opportunities under the FIA’s ADUO [Additional Development and Upgrade Opportunities] safety net, a scenario Honda will have to consider is whether or not its current power unit design is up to task.

“Well, it’s quite difficult to say, but at least we need to improve not only the reliability but also the performance,” he said, when asked if a revised power unit design for ’27 might be needed, or whether the current design can be upgraded to become competitive.

“Under current regulations, it’s difficult to improve the performance itself, so currently we are focused on how to improve the reliability, and also, within the rules, we have to improve the performance. Yes, that’s it.”

Of course, for Aston Martin, the challenge the team is facing is unlocking performance while attempting to help Honda mitigate the vibration issues, but that hasn’t stopped the squad from pushing on the chassis and aerodynamics front.

Indeed, in Japan, Aston Martin rolled out a revised front wing and floor body, and chief trackside officer Mike Krack said there’s no reason not to keep up the normal pursuit of performance alongside the work with Honda to establish reliability.

“It is true that we have to focus on reliability,” he said, “but it is also true that we are not fast enough because, even if we finish the race, we are not strong enough to finish in the points.

“On the PU side, we have, obviously, to wait, because the regulation does not allow you to make any kind of changes in the time as you like.

“On the chassis side, we are working flat out to make it faster.”

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