Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a part that helps control how much air gets into the engine. This code means there's a problem with the sensor that tells the car how open or closed this part is.
The throttle valve potentiometer measures the position of the throttle valve and sends this information to the engine control unit (ECU). A 'circuit low' code indicates that the signal from this sensor is lower than expected.
The P1590 code is triggered when the Engine Control Module (ECM) detects that the voltage signal from the throttle valve 2 potentiometer 1/2 is below the specified range. This could indicate a short to ground or an open circuit in the wiring or sensor.
• Check Engine Light is on
• Poor engine performance
• Hesitation or stalling
• Faulty throttle position sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM
Throttle Valve: A component that controls the amount of air entering the engine.
Potentiometer: A sensor that measures the position of a moving part and sends a signal to the control unit.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the throttle position sensor voltage
• Repair or replace damaged wiring or connectors
• Replace the throttle position sensor
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Volkswagen Passat
• Audi A4
• BMW 3 Series
• Regularly inspect and maintain wiring harnesses
• Keep throttle body clean
• Perform routine vehicle diagnostics
Sensor Issue
• Drive cautiously and avoid heavy acceleration
• Schedule a diagnostic appointment with a mechanic
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has been associated with throttle position sensor failures in older vehicle models, leading to enhanced sensor designs in newer models.
Moderate – While the vehicle may still be drivable, it can lead to poor performance and increased emissions.
Driving with a faulty throttle position sensor can lead to increased emissions and may not comply with local emissions regulations.
• Engine at operating temperature
• Vehicle in idle or low-speed conditions
The throttle position sensor is usually located on the throttle body, which is connected to the intake manifold.
Q: Can I drive with code P1590?
A: It's possible to drive, but it's not recommended as it may cause poor performance and higher emissions.
Q: How do I clear the P1590 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed to prevent it from returning.
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