Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer is having trouble understanding how much you're pressing the gas pedal. It's like when you can't tell how fast you're going on a bike because the speedometer is broken.
The engine control module (ECM) has detected that the signals from the throttle position sensors A and B are not within the expected range.
The P1125 code indicates a discrepancy between the expected and actual signals from the throttle position sensors A and B. These sensors provide the ECM with data on the position of the throttle, which is crucial for managing engine performance. A small error suggests that the signals are close to expected values but still outside the acceptable range.
• Check Engine Light is on
• Poor engine performance
• Hesitation or stalling during acceleration
• Faulty throttle position sensor
• Wiring issues or poor connections in the sensor circuit
• ECM malfunction
Throttle Position Sensor: A sensor that monitors the position of the throttle in an internal combustion engine.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the P1125 code.
• Inspect the wiring and connections for the throttle position sensors.
• Test the throttle position sensors for proper function.
• Replace the faulty throttle position sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Pontiac Grand Prix
• Regularly inspect and clean throttle body and sensors.
• Ensure wiring and connectors are secure and free of corrosion.
• Perform routine engine diagnostics.
Sensor Issue
• Avoid driving at high speeds until the issue is resolved.
• Get the vehicle inspected by a professional mechanic.
• Monitor for changes in vehicle performance.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been commonly reported in vehicles with electronic throttle control systems, especially in models from the early 2000s.
Moderate – It is advisable to address this issue soon to avoid potential drivability problems.
Ignoring this code may lead to reduced engine performance and could impact vehicle safety. Always consult a professional mechanic for repairs.
• Engine at normal operating temperature
• Vehicle in park or neutral
The throttle position sensors are typically located on the throttle body, which is connected to the intake manifold.
Q: Can I drive with a P1125 code?
A: It's possible to drive short distances, but it's best to get it checked soon to prevent further issues.
Q: Will a P1125 code affect fuel economy?
A: Yes, it can lead to poor fuel economy due to incorrect throttle position readings.
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