P0099 2018 GMC Sierra Code - Intake Air Temperature Sensor 2 Circuit Intermittent
Quick Answer
The P0099 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates a problem with the Intake Air Temperature Sensor 2 Circuit being intermittent. Common causes include Faulty Intake Air Temperature Sensor: The sensor itself may be malfunctioning, sending incorrect signals to the ECM, Wiring Issues: Damaged or corroded wiring connections between the sensor and ECM can cause intermittent signal disruptions, Poor Electrical Connections: Loose or poor electrical connections at the sensor or ECM can lead to intermittent circuit issues. 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
- P0099 2018 GMC Sierra indicates Intake Air Temperature Sensor 2 Circuit Intermittent.
- Common causes
- Common causes include Faulty Intake Air Temperature Sensor: The sensor itself may be malfunctioning, sending incorrect signals to the ECM, Wiring Issues: Damaged or corroded wiring connections between the sensor and ECM can cause intermittent signal disruptions, Poor Electrical Connections: Loose or poor electrical connections at the sensor or ECM can lead to intermittent circuit issues.
- 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.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0099 2018 GMC Sierra Description
The P0099 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates a problem with the Intake Air Temperature Sensor 2 Circuit being intermittent. The Intake Air Temperature Sensor (IAT) is a crucial component in the engine's air intake system that measures the temperature of the incoming air. This information is used by the engine control module (ECM) to adjust fuel delivery and ignition timing to optimize performance and fuel efficiency.
Common Causes of P0099 2018 GMC Sierra
- Faulty Intake Air Temperature Sensor: The sensor itself may be malfunctioning, sending incorrect signals to the ECM.
- Wiring Issues: Damaged or corroded wiring connections between the sensor and ECM can cause intermittent signal disruptions.
- Poor Electrical Connections: Loose or poor electrical connections at the sensor or ECM can lead to intermittent circuit issues.
- ECM Malfunction: A malfunctioning ECM may not be able to interpret the sensor signals correctly, triggering the P0099 code.
- Environmental Factors: Extreme temperatures or moisture in the intake air can affect sensor readings and trigger the code.
Symptoms of P0099 2018 GMC Sierra
- Check Engine Light: The most common symptom associated with the P0099 code is the illumination of the Check Engine Light on the vehicle's dashboard.
- Reduced Engine Performance: The engine may experience a decrease in power output or acceleration due to incorrect fuel delivery.
- Poor Fuel Efficiency: The vehicle may consume more fuel than usual, leading to decreased fuel efficiency.
- Rough Idle: The engine may idle roughly or inconsistently, indicating issues with fuel mixture and combustion.
- Stalling: In severe cases, the engine may stall or have difficulty starting due to incorrect sensor readings.
How to Fix P0099 2018 GMC Sierra
- Diagnose the Issue: Use a diagnostic scanner to retrieve the specific DTCs and perform a visual inspection of the sensor and wiring connections.
- Test the Sensor: Test the Intake Air Temperature Sensor 2 using a multimeter to check for proper resistance values and signal output.
- Check Wiring: Inspect the wiring harness for any damage, corrosion, or loose connections, repairing or replacing as necessary.
- Replace Sensor: If the sensor is faulty, replace it with a new, OEM-quality Intake Air Temperature Sensor 2.
- Clear Codes and Test: Clear the DTCs from the ECM memory, start the vehicle, and ensure the Check Engine Light does not reappear. Test drive the vehicle to verify proper operation.
Cost to Fix P0099 2018 GMC Sierra
The typical repair costs for addressing a P0099 code on a 2018 GMC Sierra can vary depending on the specific cause of the issue. In general, the cost of replacing the Intake Air Temperature Sensor 2 and addressing any wiring issues can range from $100 to $300 for parts and labor. Additional costs may apply if other components need replacement or if further diagnostics are required.
Tech Notes for P0099 2018 GMC Sierra
User Submitted Video
Need more information about the P0099 2018 GMC Sierra code?
Need more information on how to fix the P0099 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0099 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0099 2018 GMC Sierra Code
1. What are the common symptoms of OBDII code P0099 in a 2018 GMC Sierra related to the Intake Air Temperature Sensor 2 Circuit Intermittent?
- Common symptoms may include rough idling, poor engine performance, reduced fuel efficiency, and potential stalling.
2. What are some possible causes of the Intake Air Temperature Sensor 2 Circuit Intermittent issue in a 2018 GMC Sierra?
- Causes can range from a faulty intake air temperature sensor, damaged wiring or connectors, to issues with the sensor's circuit.
3. How can I diagnose the Intake Air Temperature Sensor 2 Circuit Intermittent problem in my 2018 GMC Sierra?
- You can use an OBDII scanner to retrieve the specific trouble code P0099, visually inspect the sensor and its wiring, and perform tests to check for proper sensor operation.
4. Is it safe to continue driving my 2018 GMC Sierra with the P0099 code related to the Intake Air Temperature Sensor issue?
- It's generally not recommended to drive with this issue as it can lead to further engine problems and potential damage if left unresolved.
5. Can I repair the Intake Air Temperature Sensor 2 Circuit Intermittent problem in my 2018 GMC Sierra myself?
- Depending on your skill level, you may be able to replace the sensor or repair wiring issues yourself. However, professional diagnosis and repair are recommended for accurate and lasting solutions.
6. Are there any quick fixes or temporary solutions for the P0099 code in a 2018 GMC Sierra?
- Quick fixes like clearing the trouble code may temporarily alleviate symptoms, but it's essential to address the root cause to prevent further issues.
7. How much does it typically cost to repair the Intake Air Temperature Sensor 2 Circuit Intermittent problem in a 2018 GMC Sierra?
- Repair costs can vary based on the specific cause of the issue, but expenses may include sensor replacement, wiring repairs, and labor charges from a mechanic.
8. Will resetting the ECU clear the P0099 trouble code associated with the Intake Air Temperature Sensor in my 2018 GMC Sierra?
- Resetting the ECU may temporarily clear the code, but if the underlying problem persists, the code is likely to reappear after driving cycles.
9. Can a bad Intake Air Temperature Sensor affect the emissions system in a 2018 GMC Sierra?
- Yes, a malfunctioning sensor can impact the air-fuel mixture, potentially leading to increased emissions, which could cause the vehicle to fail emissions tests.
10. What steps should I take if the P0099 code related to the Intake Air Temperature Sensor issue keeps recurring in my 2018 GMC Sierra after repairs?
- If the code persists after repairs, it's advisable to have a professional mechanic conduct a thorough diagnostic to identify any underlying issues that may have been overlooked during previous repairs.
Discuss the causes and fixes for P0099 2018 GMC Sierra OBDII Code
Code P0099 2018 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.