Williams under FIA scrutiny as Carlos Sainz FW48 clears extensive Miami checks

Carlos Sainz’s Williams FW48, including its front wing adjuster system, passed the FIA post-race tests after randomly undergoing extensive testing at the Miami Grand Prix.

The race marked the first time this season that both Williams FW48 cars finished inside the top ten, with Sainz ninth across the line ahead of his teammate Alex Albon.

Carlos Sainz’s Williams passes FIA testing

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Every race the FIA’s technical delegate Jo Bauer randomly choses cars to go through extensive post-race testing.

Rather than just being weighed, the cars undergo extensive scrutineering on different areas of the cars.

In Miami, Sainz’s Williams was one of the cars pulled aside, with the FIA checking the FW48’s front wing adjuster system as well as the attached sensors.

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“After the race in Miami,” read the FIA note, “car number 55 was randomly chosen among the top ten cars for more extensive physical inspections.

“Subject to these physical inspections was the front wing adjuster system as well as the attached sensors, their loom routing and connections to the standard ECU.

“In relation to Article C3.10.10, the following items were checked:

“Number and type of actuators and sensors.

“Connection to the FIA standard ECU.

“Installation of sensors.

“In relation to Article C8, the following items were checked:

“Identification of sensors and actuator values.

“Homologation status of sensor and actuator values.

“Data logging of signals.

“FIA-F1-DOC-001-F-submissions.

“All inspected components were found to be in conformance with the 2026 Formula One Technical Regulations.”

Sainz brought in his second P9 of the season in Miami, while his teammate Albon made it a double points-haul for Williams with tenth place.

The team moved up to seventh in the Constructors’ Championship on five points, three ahead of newcomers Audi.

Earlier this year the FIA’s scrutineering was questioned when Red Bull driver Isack Hadjar was thrown out of qualifying due to a technical infringement at the Miami Grand Prix.

The stewards found a small section of the left and right-hand side floorboard was protruding outside of the permitted reference volume by 2mm and thus contravened the regulations.

As a result, Hadjar was disqualified from qualifying.

Despite his DSQ, his teammate Max Verstappen’s car wasn’t put through additional checks. Red Bull team boss Laurent Mekies said it was just a mistake on Red Bull’s part.

“They were on the exact same spec,” Mekies told media including PlanetF1.com. “We made a mistake in Isack’s car.

“It’s very simple, the car was found to be two millimetres too wide. We should have spotted it earlier in our routine checks. We did not and it’s painful but it’s easy to fix.”

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