P0638 on Ford: How to Diagnose & Fix
Throttle Actuator Control Range/Performance Bank 1
1 Ford model · 1 documented issue · 1 critical · $250-$550 repair
P0638 on Ford by model: symptoms, diagnosis and fix
The electronic throttle body suffers internal contamination/wear of the motor contacts, causing intermittent electrical failure rather than simple dirt buildup. The result is a sudden loss of power (limp/failsafe mode) with the amber wrench (powertrain) warning light, rough idle, or stalling, sometimes in traffic. Ford acknowledged the problem with extended-warranty program 13N03 for 2010-2013 models and Customer Satisfaction Program 16B32 for certain 2015-2016 vehicles including Fusion.
Common Symptoms
- Wrench/powertrain warning light
- Sudden loss of power / limp mode
- Rough or surging idle
- Stalling
- Reduced throttle response
How to Fix
For the limp-mode failure the throttle body must be replaced (cleaning does not fix internal electronic wear), followed by a mandatory throttle-body relearn to prevent high idle and driveability faults. Check whether the vehicle qualified for 13N03 or 16B32 coverage history.
Sources for this issue (2)
P0638 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0638 mean on a Ford?
P0638 stands for "Throttle Actuator Control Range/Performance Bank 1." This code means the engine computer detected that the electronic throttle plate (Bank 1) is not opening or closing to the position it commanded. The PCM monitors throttle actuator position against the desired angle and sets this code when they disagree. This can trigger reduced-power 'limp' mode, hesitation, or unexpected changes in engine response, which makes it a safety-relevant fault. On Ford it is documented across 1 model: Fusion.
What are the most common causes of P0638?
The most common causes of P0638 are: Dirty or carbon-clogged throttle body, Faulty throttle actuator motor, Failed throttle position sensor, Corroded or loose throttle body connector, Wiring faults in the throttle control circuit, Mechanical binding of the throttle plate, PCM fault. The specific cause varies by vehicle.
How much does it cost to fix P0638 on a Ford?
Published repair estimates on Ford range from $250 to $550 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0638 on a different make?
View P0638 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.