OBD-II code · Powertrain (generic, extended)

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.

Is it safe to drive with P2174?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyIntake severely restricted

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
0.3–2.5 h
Emissions test
Likely to fail
Parts involved
Electronic Throttle Body, Mass Air Flow Sensor

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.