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 the computer in the car is having trouble getting a steady reading from a sensor that measures the temperature of the air going into the engine. It's like trying to read a thermometer that keeps changing its numbers too quickly.
The P0099 code is triggered when the Engine Control Module (ECM) detects an intermittent or erratic signal from the Intake Air Temperature (IAT) Sensor 2 on Bank 1.
The Intake Air Temperature Sensor 2 is responsible for measuring the temperature of the air entering the engine. This information helps the ECM adjust the air-fuel mixture for optimal combustion. An intermittent or erratic signal indicates a problem with the sensor circuit, which can affect engine performance.
• Check Engine Light illuminated
• Poor fuel economy
• Rough idle or engine performance issues
• Faulty Intake Air Temperature Sensor 2
• Wiring issues such as damaged wires or poor connections
• Faulty ECM or software issues
ECM: Engine Control Module
IAT Sensor: Intake Air Temperature Sensor
• Use an OBD-II scanner to confirm the code.
• Inspect the IAT Sensor 2 and its wiring for damage or loose connections.
• Test the sensor's resistance and compare it to manufacturer specifications.
• Replace the faulty IAT Sensor 2.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the ECM if necessary.
• OBD-II Scanner
• Multimeter
• Basic hand tools (screwdrivers, pliers)
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain sensor connections.
• Keep the air intake system clean.
• Perform regular vehicle diagnostics.
Sensor Issue
• Avoid driving with the Check Engine Light on for extended periods.
• Consult a professional mechanic if unsure about repairs.
Repairs may be covered under the vehicle's emissions warranty if applicable.
This code has been associated with sensor reliability issues in certain vehicle models, leading to manufacturer recalls or service bulletins.
Moderate – It should be addressed soon to prevent potential engine performance issues.
Driving with a malfunctioning sensor can lead to increased emissions and may fail emissions testing.
• Engine at operating temperature
• Vehicle stationary or at idle
The Intake Air Temperature Sensor 2 is typically located in the air intake duct or manifold on Bank 1 of the engine.
Q: Can I drive with a P0099 code?
A: While you can drive with this code, it's best to fix it soon to avoid potential engine performance issues.
Q: How does the IAT sensor affect my car?
A: The IAT sensor helps the engine control module adjust the air-fuel mixture for efficient combustion, affecting performance and fuel economy.
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