Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car has a part called the EGR valve that helps reduce pollution. This code means that the valve is stuck open, letting too much exhaust gas go back into the engine, which can cause problems.
The EGR valve is supposed to open and close at specific times to control the flow of exhaust gases back into the engine. If it gets stuck open, it can cause the engine to run poorly.
The P042E code indicates that the Powertrain Control Module (PCM) has detected that the EGR valve is not closing as it should. This can result in excessive exhaust gases being recirculated into the combustion chamber, leading to inefficient combustion and potential engine performance issues.
• Rough engine idle
• Decreased fuel efficiency
• Check Engine Light illuminated
• Faulty EGR valve
• Carbon buildup in EGR valve
• Faulty EGR solenoid
EGR: Exhaust Gas Recirculation
PCM: Powertrain Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the EGR valve for carbon buildup or damage.
• Test the EGR solenoid for proper operation.
• Clean the EGR valve to remove carbon buildup.
• Replace the EGR valve if it is faulty.
• Replace the EGR solenoid if it is not functioning correctly.
• OBD-II scanner
• Wrench set
• Carbon cleaner
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly clean the EGR valve.
• Use quality fuel to minimize carbon buildup.
• Perform routine engine maintenance.
Engine Performance
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent this issue.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
The EGR system has been used in vehicles for decades to help reduce emissions by recirculating a portion of the exhaust gases back into the engine cylinders.
Moderate – It should be addressed soon to avoid potential engine performance issues.
Driving with a malfunctioning EGR system can lead to increased emissions, which may not comply with local environmental regulations.
• Engine at operating temperature
• Idle conditions
The EGR valve is typically located on the engine, near the intake manifold.
Q: Can I drive with a P042E code?
A: While you can drive with this code, it's not recommended as it can lead to decreased engine performance and increased emissions.
Q: What happens if I ignore the P042E code?
A: Ignoring the code can lead to poor engine performance, reduced fuel efficiency, and potential damage to other engine components.
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