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 there's a problem with the part of the car that helps control how much air goes into the engine. It's like a door that opens and closes to let air in, and something is wrong with the motor that moves this door.
The throttle actuator control motor is responsible for controlling the throttle plate. If there's an open circuit, it means the motor isn't getting power or the signal it needs to operate.
P3191 indicates that the ECM (Engine Control Module) has detected an open circuit in the throttle actuator control motor circuit for Bank 2. This can be due to a wiring issue, a faulty throttle actuator motor, or a problem with the ECM itself.
• Check Engine Light is on
• Poor engine performance
• Engine stalling or hesitation
• Faulty throttle actuator control motor
• Open or shorted wiring in the throttle actuator circuit
• Faulty ECM
Throttle Actuator: A device that controls the throttle plate in an engine.
ECM: Engine Control Module, the computer that controls engine functions.
• Check for any other related codes and address them first.
• Inspect the wiring and connectors for the throttle actuator control motor.
• Test the throttle actuator control motor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the throttle actuator control motor if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Lexus RX
• Toyota Camry
• Regular maintenance and inspection of the throttle body.
• Ensure electrical connections are secure.
• Use quality parts for replacements.
Engine Performance
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle if it shows severe symptoms.
Check with your vehicle manufacturer for specific warranty coverage related to throttle system components.
P3191 has been reported in various models, often related to issues with throttle body components in hybrid vehicles.
Moderate – While the vehicle may still be drivable, it can lead to poor performance and should be addressed soon.
Driving with a malfunctioning throttle actuator can lead to unsafe driving conditions. Address the issue promptly to ensure vehicle safety.
• Engine running
• Throttle system engaged
The throttle actuator is typically located on the throttle body, which is connected to the intake manifold.
Q: Can I drive with a P3191 code?
A: It's not recommended as it can cause poor performance and potentially unsafe driving conditions.
Q: What happens if I ignore the P3191 code?
A: Ignoring the code can lead to worsening engine performance and possible stalling.
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