The U.S. National Highway Traffic Safety Administration announced Thursday that it has officially closed a preliminary investigation it opened in 2022 into 695,000 Tesla vehicles that were experiencing sudden, unexpected deceleration.
The probe focused on Tesla’s Model 3 and Model Y vehicles, and regulators said the decision to close the case was based on the low level of danger posed to drivers and a significant decrease in the number of complaints received.
According to the agency, Tesla rolled out software updates in early 2022 specifically designed to address the unexpected slowing issue. The updates appear to have made a measurable difference — when the investigation first launched, there were 300 incident reports on file. That number fell to 45 in 2024, dropped further to 19 in 2025, and only three reports have come in since the beginning of 2026.
Regulators also noted that the sudden deceleration events did not cause vehicles to drift out of their lanes, nor did they result in dangerous reductions in following distance that could have led to rear-end collisions.
This closure comes just one week after the same agency separately wrapped up an expanded investigation into approximately 376,241 Model 3 and Model Y vehicles that had been flagged for issues related to loss of steering control.
