P1111 2018 GMC Sierra Code - Intake Air Temperature Sensor Circuit Intermittent High Voltage
Quick Answer
The P1111 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates an issue with the Intake Air Temperature (IAT) Sensor Circuit intermittently reporting high voltage. Common causes include Faulty Intake Air Temperature (IAT) sensor, Damaged wiring or connectors in the IAT sensor circuit, ECM malfunction. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1111 2018 GMC Sierra indicates Intake Air Temperature Sensor Circuit Intermittent High Voltage.
- Common causes
- Common causes include Faulty Intake Air Temperature (IAT) sensor, Damaged wiring or connectors in the IAT sensor circuit, ECM malfunction.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P1111 2018 GMC Sierra Description
The P1111 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates an issue with the Intake Air Temperature (IAT) Sensor Circuit intermittently reporting high voltage. The IAT sensor is a crucial component of the vehicle's engine management system, as it measures the temperature of the incoming air to the engine. This information is used by the engine control module (ECM) to adjust fuel delivery and ignition timing for optimal performance and efficiency.
Common Causes of P1111 2018 GMC Sierra
- Faulty Intake Air Temperature (IAT) sensor
- Damaged wiring or connectors in the IAT sensor circuit
- ECM malfunction
- Intake air leaks near the sensor
- Incorrect sensor placement or mounting
Symptoms of P1111 2018 GMC Sierra
- Decreased fuel efficiency
- Rough idling or hesitation during acceleration
- Engine stalling or misfiring
- Check Engine Light illuminated
- Reduced engine performance
How to Fix P1111 2018 GMC Sierra
- Begin by visually inspecting the wiring and connectors in the IAT sensor circuit for any signs of damage or corrosion. Repair or replace any damaged components.
- Test the IAT sensor using a multimeter to ensure it is functioning correctly. Replace the sensor if it is faulty.
- Clear the DTC and reset the ECM to see if the code returns. If it does, further diagnosis may be required to identify the root cause.
- Check for any intake air leaks near the sensor that could be affecting its readings. Repair any leaks found.
- If the issue persists, consult a professional mechanic or dealership for further diagnosis and potential ECM replacement if necessary.
Cost to Fix P1111 2018 GMC Sierra
The typical repair costs for addressing a P1111 code on a 2018 GMC Sierra can vary depending on the specific cause of the issue. Replacement of the IAT sensor itself can cost between $50 and $150, while labor costs can range from $50 to $150 per hour. Additional costs may be incurred if wiring or connectors need to be repaired or replaced, or if the ECM requires replacement. Overall, the total repair cost could range from $100 to $500 or more, depending on the extent of the issue and the necessary repairs. It is advisable to consult with a trusted mechanic or dealership for a more accurate estimate based on the specific circumstances of the vehicle.
Tech Notes for P1111 2018 GMC Sierra
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