Powertrain
generic / SAE
P2174
Throttle Actuator Control System - Sudden Low Air Flow Detected
A sudden, large drop in MAF/MAP signal not matched by a pedal change — typically intake restriction, MAF failure, or actively-stuck-closed throttle plate.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number1 / 74
Possible causes
- Intake severely restricted high
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 40–600 €
- Estimated time: 0.3–2.5 h
- Component: electronic throttle body
- Component: mass air flow sensor
- MIL / check engine light
- emissions-relevant
- limp mode possible
Sources
References
sae:J2012