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 car's computer is having trouble with a part that controls how much pressure is in the exhaust. It's like when you have a whistle that sometimes works and sometimes doesn't.
The code P0479 indicates an issue with the exhaust pressure control valve, which is not consistently operating as expected.
P0479 is a diagnostic trouble code (DTC) for 'Exhaust Pressure Control Valve A Intermittent.' This means the engine control module (ECM) has detected an intermittent fault in the exhaust pressure control valve circuit. The valve is responsible for regulating exhaust pressure, which is crucial for engine efficiency and emissions control.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty exhaust pressure control valve
• Wiring issues or poor connections in the valve circuit
• Faulty ECM or software issues
ECM: Engine Control Module
DTC: Diagnostic Trouble Code
• Check for any other related trouble codes
• Inspect the wiring and connections to the exhaust pressure control valve
• Test the exhaust pressure control valve for proper operation
• Repair or replace faulty wiring or connectors
• Replace the exhaust pressure control valve
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-Series
• Chevrolet Silverado
• Dodge Ram
• Regular maintenance of the exhaust system
• Check and clean exhaust components periodically
• Ensure proper electrical connections
Engine Performance
• Do not ignore the Check Engine Light
• Seek professional diagnostic services if unsure
• Consider regular vehicle inspections
Check with the vehicle manufacturer for specific warranty coverage related to emissions components.
This code has been associated with vehicles that have exhaust system modifications or have experienced wear and tear over time.
Moderate – It is advisable to address this issue to prevent potential damage to the engine and ensure optimal performance.
Driving with a malfunctioning exhaust pressure control valve can lead to increased emissions, which may not comply with local regulations.
• Engine at operating temperature
• Vehicle in a safe and stable position
The exhaust pressure control valve is typically located near the exhaust manifold or turbocharger.
Q: Can I drive with a P0479 code?
A: While the car may still be drivable, it's best to address the issue to avoid potential engine damage and increased emissions.
Q: What happens if I ignore the P0479 code?
A: Ignoring the code can lead to poor engine performance, higher emissions, and potential damage to the exhaust system.
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