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 part of the car that helps reduce pollution. It's like a door that should open and close, but it's stuck or not working right.
The P0403 code indicates a malfunction in the EGR system's control circuit, which is responsible for recirculating a portion of the exhaust gases back into the engine to reduce emissions.
The EGR system reduces nitrogen oxide emissions by recirculating a portion of the exhaust gases back into the engine cylinders. The EGR valve's control circuit is responsible for opening and closing the valve as needed. A P0403 code is set when the Engine Control Module (ECM) detects an open circuit or malfunction in the EGR control circuit.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty EGR valve
• Damaged or corroded wiring/connectors
• Faulty EGR solenoid
EGR: Exhaust Gas Recirculation
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code
• Inspect the EGR valve and wiring for damage
• Test the EGR solenoid for proper operation
• Replace the faulty EGR valve
• Repair or replace damaged wiring/connectors
• Replace the EGR solenoid if defective
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Toyota Camry
• Ford F-150
• Honda Accord
• Regular maintenance of the EGR system
• Use high-quality fuel
• Keep the engine clean and well-tuned
Sensor Issue
• Address the issue promptly to avoid increased emissions
• Consult a professional mechanic if unsure about repairs
Check vehicle warranty for emissions-related components coverage.
The P0403 code has been common in vehicles with EGR systems for emissions control since the introduction of OBD-II standards.
Moderate – Should be addressed to prevent potential damage to the engine and increased emissions.
Ignoring emissions-related codes can lead to failing emissions tests and potential fines.
• Engine at operating temperature
• Vehicle in closed-loop mode
The EGR valve is typically located on or near the intake manifold.
Q: Can I drive with a P0403 code?
A: It's possible, but not recommended as it may lead to increased emissions and reduced engine performance.
Q: Will a P0403 code affect my fuel economy?
A: Yes, it can lead to decreased fuel efficiency due to improper exhaust gas recirculation.
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