Jeep Wranglers across four model years are being investigated over an engine issue that can cause a power shutdown.

The probe takes in more than 94,000 Wrangler model years 2021 through 2024.

The original recall addressed the engine shutdown in 2021 to 2023 4XE models. But complaints that filtered in after recall repairs indicate the remedies failed to address the problem, according to the National Highway Traffic Safety Administration, which said other post-recall complaints involved units not included in the recall, and that in fact there have been more complaints about the latter category.

The federal regulator is looking into any defects in the vehicles not included in the recall, along with determining whether the recall was effective for the vehicles included in it.

The investigation affects 2021 to 2024 Wranglers, 2022 to 2024 Wrangler 4XEs, and 2021 Wrangle PHEVs.

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