Ford Bronco Sport 2020–2021 — technical service bulletin
Bulletin SSM 49930 · NHTSA communication 10199501 · issued Jul 5, 2021
Technical service bulletin
communication type
Engine and Engine Cooling
component
2020–2021
model years
3
vehicle entries
Official summary
Some 2020-2021 Escape and 2021 Bronco Sport vehicles equipped with the 1.5L engine may exhibit a lugging vibration and/or boom noise while driving in gears 5-8 at approximately 1500 engine revolutions per minute (RPM). This may be felt more when the engine is under a light to moderate load. A vibration and/or boom noise could be generated from the firing frequency of the 3 cylinders or when cylinder deactivation occurs and the engine is running on 2 cylinders. Compare to a like vehicle before attempting to diagnose as this condition may be characteristic. Setting the vehicle's drive mode to SP
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.