Some 2021-2023 F-150 non-Lightning vehicles may exhibit reduced power and/or lack of acceleration above 4000 revolutions per minute (RPM) and/or not being able to shift above 4000 RPM. This may be due to the missing retainers (service part number W714040-S300) from the air cleaner intake. Prior to performing other diagnostics, inspect the air cleaner intake to determine if the retainers are present and fully seated. If the retainers are not present, install as necessary. Refer to the Workshop Manual (WSM), Section 303-12C Intake Air Distribution and Filtering - 3.5L EcoBoost (BM), Removal and Installation, Air Cleaner, Removal, Step 4. If the retainers are present, or the missing retainers were replaced and the symptom is still present, refer to the WSM for additional diagnostics. For claiming, use causal part 9C675 and applicable labor operations in Section 06 of the Service Labor Time Standards (SLTS) Manual.
