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P0121 on FORD F-150

Severity
Medium
NHTSA Reports
2
Most Affected
2005

What P0121 Means on Your FORD F-150

Real FORD F-150 Owner Reports (Source: NHTSA Complaints Database)

"2005 ford f150 vehicle loses power and all control while driving on the road. this happened at least six times. very lucky traffic was light most times but one almost a caused rear end collision."

— 2005 FORD F-150 owner • VEHICLE SPEED CONTROL • Filed 08/12/2009

"While driving 35 mph my ford f150 truck engine shut down. the truck lost all power brakes and steering. seconds before it stalled a engine malfunction light came on. i was only able to re-start after coming to a complete stop, placing the truck in park and turning the key off then back on."

— 2005 FORD F-150 owner • ELECTRICAL SYSTEM • Filed 01/08/2009

Data from NHTSA Vehicle Complaints Database. All reports are filed by vehicle owners directly with the U.S. Department of Transportation.

Common Causes of P0121 on FORD F-150

50%
50%

Percentages based on NHTSA complaint component analysis for this vehicle.

Complaint Trend by Year

2005
2

What To Do Next

  1. 1
    Check for recalls on YOUR VIN

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if your vehicle is covered.

  2. 2
    Get a proper diagnosis

    A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50-$150) pinpoints the root cause before you spend money on parts.

  3. 3
    Compare repair quotes

    Get 2-3 quotes. Dealer vs independent shop prices often differ 30-50% for the same repair.

P0121 on Other Vehicles

Data sourced from the National Highway Traffic Safety Administration (U.S. Department of Transportation) and the SAE J2012 OBD-II standard. Code definitions follow the SAE J2012 / ISO 15031-6 standard. Owner reports are filed directly with NHTSA by vehicle owners. This information is provided for educational purposes only and should not replace professional automotive diagnosis. Always consult a qualified mechanic for vehicle repair decisions.

Last updated: March 2026