Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a sensor in the car that checks how hot the exhaust is. It's like a thermometer for the car's exhaust, and it's not working right.
The P1490 code indicates an electrical issue with the Exhaust Gas Temperature (EGT) Sensor 'A'. This sensor measures the temperature of the exhaust gases to ensure the engine is running efficiently and to protect components from overheating.
The Exhaust Gas Temperature Sensor 'A' is responsible for measuring the temperature of the exhaust gases leaving the engine. This information is used by the engine control module (ECM) to adjust fuel injection and timing. An electrical problem with this sensor can cause incorrect temperature readings, affecting engine performance and emissions.
• Check Engine Light is on
• Poor fuel economy
• Reduced engine performance
• Faulty Exhaust Gas Temperature Sensor
• Wiring issues such as shorts or open circuits
• Corroded or damaged connectors
Exhaust Gas Temperature Sensor: A sensor that measures the temperature of the exhaust gases.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage or corrosion
• Test the Exhaust Gas Temperature Sensor with a multimeter
• Replace the faulty Exhaust Gas Temperature Sensor
• Repair or replace damaged wiring or connectors
• Clear the code and test drive the vehicle to ensure the issue is resolved
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Volkswagen Jetta
• Audi A4
• BMW 3 Series
• Regularly inspect and maintain the exhaust system
• Ensure sensors are clean and free from debris
• Check wiring and connectors for wear and tear
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on
• Avoid prolonged driving with this code active to prevent further damage
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with issues in vehicles with advanced emissions control systems, particularly in diesel engines.
Moderate – It should be addressed soon to prevent potential damage to the exhaust system and ensure optimal engine performance.
Driving with a malfunctioning exhaust gas temperature sensor may lead to increased emissions, which can be illegal in some areas.
• Engine at operating temperature
• Vehicle stationary with engine idling
The Exhaust Gas Temperature Sensor 'A' is typically located in the exhaust manifold or downpipe, near the turbocharger if equipped.
Q: Can I drive with a P1490 code?
A: It's not recommended to drive for extended periods with this code active, as it can lead to further engine or exhaust system issues.
Q: How do I reset the Check Engine Light after repair?
A: Use an OBD-II scanner to clear the code after the repair is completed.
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