What Does P2174 Mean?
The PCM has detected a sudden, unexpected decrease in airflow through the throttle body that doesn't correlate with commanded throttle position. This suggests throttle body obstruction, icing, or actuator failure.
Safety Warning
Sudden loss of power during acceleration creates serious safety hazard. Vehicle may stall or fail to accelerate in traffic. Repair immediately.
Common Causes
30%
Throttle body icing in cold weather conditions
25%
Severe carbon buildup restricting throttle opening
20%
Failed electronic throttle actuator or binding mechanism
15%
Clogged or restricted air filter
10%
Faulty MAF sensor reporting incorrect low airflow
Diagnostic Steps
1
Step 1: Inspect air filter for excessive dirt or restriction and replace if needed
2
Step 2: Remove throttle body and inspect for carbon buildup, damage, or obstructions
3
Step 3: Check for throttle body icing (if conditions are near freezing with high humidity)
4
Step 4: Test throttle actuator by commanding various throttle positions with scan tool
5
Step 5: Monitor MAF sensor readings during acceleration and compare to normal values
Estimated Repair Cost
$80 - $800
Parts + labor, varies by vehicle and location
The PCM has detected a sudden, unexpected decrease in airflow through the throttle body that doesn't correlate with commanded throttle position. This suggests throttle body obstruction, icing, or actuator failure.
The most common cause of P2174 (Throttle Actuator Control System - Sudden Low Air Flow Detected) is: Throttle body icing in cold weather conditions
Typical repair costs for P2174 range from $80 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Sudden loss of power during acceleration creates serious safety hazard. Vehicle may stall or fail to accelerate in traffic. Repair immediately.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2174 to identify the root cause.
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Quick Info
Category
Powertrain
System
Air Intake and Throttle Control System
Difficulty
Type
Generic (SAE)
Recommended Tools
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