OBD-II code · Powertrain (generic)
P0638 Throttle Actuator Control Range or Performance Bank 1
The drive-by-wire throttle actuator on bank 1 does not respond as commanded - actuator slow, gearing slipping, or position feedback offset against actual blade angle.
Is it safe to drive with P0638?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyActuator sticking due to carbon
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 1–3.5 h
- Emissions test
- Likely to fail
- Parts involved
- Throttle Actuator B1, Throttle Position Sensor B1
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.