Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer noticed a sudden drop in the amount of air going into the engine. It's like if you were trying to breathe through a straw and someone pinched it shut suddenly.
The engine control module (ECM) detected a sudden decrease in air flow through the throttle body that was not expected based on the throttle position.
The P2174 code indicates that the throttle actuator control system has detected a sudden drop in air flow. This is monitored by the ECM using sensors that measure air flow and throttle position. If the air flow drops unexpectedly, it can affect engine performance and emissions.
• Check Engine Light is on
• Reduced engine power
• Engine stalling or hesitation
• Faulty throttle body
• Throttle position sensor malfunction
• Air intake blockage
Throttle Body: A component of the air intake system that controls the amount of air flowing into the engine.
ECM: Engine Control Module, the computer that manages engine operations.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle body for damage or blockage.
• Check the throttle position sensor for proper operation.
• Clean or replace the throttle body.
• Replace the throttle position sensor if faulty.
• Clear any blockages in the air intake system.
• OBD-II scanner
• Multimeter
• Throttle body cleaner
$150 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance of the air intake system
• Periodic cleaning of the throttle body
• Routine inspection of sensors
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle aggressively until repaired.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been more prevalent in vehicles with electronic throttle control systems, as they rely heavily on sensors and actuators.
Moderate – It should be addressed soon to avoid potential engine performance issues.
Driving with a malfunctioning throttle control system can lead to unsafe driving conditions and may not comply with emissions regulations.
• Engine running
• Throttle position changes
The throttle body is typically located between the air filter and the intake manifold.
Q: Can I drive with a P2174 code?
A: It's not recommended to drive for extended periods with this code as it can affect engine performance.
Q: How serious is the P2174 code?
A: While not immediately critical, it should be addressed to prevent further engine issues.
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Fitment Required · Vehicle-fitment part
Relevant for airflow, fuel-trim, and intake-metering faults after confirming the sensor is actually at fault.
Airflow and fuel-trim codes can involve the mass air flow sensor after proper diagnosis.
Verify the sensor design and fitment for your exact vehicle.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.