Oscar Piastri confirms ‘fuel-systems issue’ behind curtailed McLaren MCL40 debut

McLaren driver Oscar Piastri has confirmed that a fuel-systems issue limited his running on the penultimate day of the first pre-season test of F1 2026 in Barcelona.

And the Australian says he has been left excited by the process of trying to understand the vastly different cars for 2026.

Oscar Piastri’s McLaren MCL40 debut restricted by ‘a few issues’ in Barcelona

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McLaren confirmed to PlanetF1.com last week that the team would miss the start of the opening pre-season test in Barcelona.

The MCL40 made its on-track debut on Wednesday with Lando Norris, the reigning world champion, behind the wheel.

Norris completed 76 laps, recording the third-fastest time, on Day 3 before handing driving duties over to Piastri for his first running of the new season.

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Piastri was classified fourth in the unofficial times, trailing George Russell by 1.974 seconds as the Mercedes driver set the fastest lap of testing so far.

The Perth-born driver was limited to a total of 48 laps after encountering “a few issues” over the course of the day.

Piastri told Formula 1: “It was nice to be back out and especially in a new car.

“A lot of new challenges for us this year up and down the grid, so it’s nice to get stuck into some of them.

“Unfortunately, a few issues today.

“We had a fuel systems issue, which cut our day a bit short, but I know the team’s working really hard to get that fixed and get us back out for as many laps as we can tomorrow.”

Put to him that there is lots to learn about the new car following an overhaul to the chassis and engine rules for 2026, he added: “Definitely the first few things are just trying to iron out all these bugs, find the problems.

“They’re all completely different cars, completely different engines to what we’ve had for the last three or four years.

“That’s part of what this test is about and I think we’ve already identified a few things we can try and improve on the car to make it feel a bit nicer.

“They’re all going to be different to what we’ve had, so just trying to find all the bugs, all the problems, and then try and make the car faster.

“It’s definitely been a challenge and exciting.

“There’s a lot of areas where you can be a point of difference and make a point of difference now, which is exciting. You’ve got to put in the hard work to make that happen.

“But like I’ve said, there’s a lot of lot of challenges for all of us up and down the grid.

“There’s going to be some aspects of these cars that we’ve never really had to do before in our careers, so there’s plenty of plenty of lessons to be learned.”

Asked what else he wants to get out of the Barcelona shakedown ahead of the final day of running, he added: “Just trying to get a better feel for what the car is like.

“There’s such a big departure from what we’ve had the last few years and all of my time in F1. There’s a lot of lot of things to understand.

“Obviously there’s new engines to understand, but just the philosophy of the car is completely different as well and less downforce.

“So just getting used to that and how different things feel, trying to get a good read on that as quickly as possible, find a good direction to make the car quicker and feel nice.

“That’s always the aim.”

In a statement issued to PlanetF1.com at the close of Thursday’s running, Mark Temple, the McLaren technical director of performance, said the team “haven’t encountered anything too unexpected” with its F1 2026 car to date.

Temple said: “Second day on track with positives to take away.

“We’ve got a good understanding of where the car is from a baseline point of view.

“In this shakedown, the most important aspect for drivers is that they understand how the new car operates, how the power unit interacts and the process of energy management.

“Oscar now has some good reference points for that, as well as a feel for how the chassis behaves.

“Overall, we haven’t encountered anything too unexpected.

“The behaviour and handling of the car is in line with what we thought, so nothing is catching the drivers out.

“It’s just about learning and getting to know it, and then as we get more time, we’ll look to try and tweak or tune the car.

“This is a shakedown and is meant to help us identify any issues so we can understand and solve them going into Bahrain, so that’s our big focus as we go into the final day tomorrow.

“Of course, it’s a shame we could not run in the afternoon as every minute of track time is precious at such an early stage of the season.

“We discovered a fuel system problem, which meant we haven’t been able to do all the running we would like.

“The car is very complex, so we decided to bring the car back into the garage and strip it down to fully understand where the problem is coming from ahead of tomorrow’s running.”

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