The P2174: Throttle Actuator Control System – Sudden Low Air Flow Detected refers to an issue where the throttle actuator control system detects an unexpected decrease in air flow. This can result from a faulty throttle actuator, a sensor problem, or mechanical issues that restrict air intake.
P2174 – Quick Overview
Code | Information |
---|---|
Meaning | P2174: Throttle Actuator Control System – Sudden Low Air Flow Detected |
Is it serious? | Yes, this can impact engine performance and lead to rough idling, stalling, or reduced power. |
Possible causes | – Sudden decrease in air flow detected by the throttle actuator – Faulty throttle actuator or sensor – Air intake restrictions or mechanical issues |
How to diagnose? | – Inspect for air intake restrictions – Test the throttle actuator and sensors – Check for mechanical issues |
P2174 Meaning
The P2174: Throttle Actuator Control System – Sudden Low Air Flow Detected code indicates that the engine control module (ECM) has detected a sudden and unexpected drop in air flow through the throttle actuator. The throttle actuator is responsible for controlling the airflow to the engine, and any restriction or malfunction can affect engine performance, causing rough idling, reduced power, or stalling.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional related codes that might give further insight into the issue. | OBD-II Scanner |
Inspect Air Intake System | Inspect the air intake system for restrictions, such as a clogged air filter, intake leaks, or blockages that could reduce airflow. | Flashlight, Safety Gloves |
Test Throttle Actuator | Use a diagnostic tool to test the throttle actuator for proper operation. Ensure it responds correctly to the ECM’s commands. | Diagnostic Tool, Multimeter |
Inspect Sensors | Inspect and test the mass air flow (MAF) sensor or manifold absolute pressure (MAP) sensor to ensure they are accurately measuring airflow. | Multimeter, Diagnostic Tool |
Check for Mechanical Issues | Inspect the throttle body and related components for mechanical issues, such as sticking or binding, that could restrict airflow. | Flashlight, Wrenches |
Repair or Replace Faulty Components | If faulty sensors, throttle actuators, or air intake components are found, repair or replace them as necessary to resolve the issue. | Replacement Parts, Tools |
Clear the Code and Test Drive | After repairs, clear the P2174 code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner |
Recheck for Codes | After the test drive, re-scan the vehicle to confirm that the P2174 code does not return. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)