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 found a problem with the sensor that checks the pressure in the fuel system. It's like when a balloon has a tiny leak and can't hold air properly.
The P147B code is triggered when the vehicle's engine control module (ECM) detects an issue with the evaporative emission (EVAP) system pressure sensor or switch. This sensor monitors the pressure in the fuel system to ensure there are no leaks.
The EVAP system pressure sensor is responsible for monitoring the pressure within the fuel tank and the EVAP system. If the ECM detects an inconsistent or unexpected signal from this sensor, it triggers the P147B code. This could be due to electrical issues, sensor malfunctions, or mechanical problems within the EVAP system.
• Check Engine Light is on
• Slight decrease in fuel efficiency
• Possible fuel smell from the vehicle
• Faulty EVAP pressure sensor
• Wiring issues or poor electrical connections
• Leaking fuel cap or EVAP system leak
EVAP: Evaporative Emission Control System, which prevents fuel vapors from escaping into the atmosphere.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the EVAP pressure sensor and its wiring for damage.
• Perform a smoke test to check for leaks in the EVAP system.
• Replace the EVAP pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the fuel cap if it is not sealing properly.
• OBD-II scanner
• Multimeter
• Smoke machine for leak detection
$100 - $300
Moderate
• Ford Focus
• Chevrolet Malibu
• Toyota Camry
• Regularly check and replace the fuel cap if necessary.
• Inspect EVAP system components during routine maintenance.
• Ensure proper electrical connections in the EVAP system.
Sensor Issue
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
The P147B code has been associated with issues in vehicles with complex EVAP systems, often due to sensor malfunctions or wiring problems.
Moderate – It should be addressed soon to avoid potential emissions issues.
Ignoring emissions-related codes can lead to increased pollution and may be illegal in certain regions.
• Vehicle at operating temperature
• Fuel tank between 25% and 75% full
The EVAP pressure sensor is typically located near the fuel tank or within the EVAP canister assembly.
Q: Can I drive with a P147B code?
A: While the car may still run, it's best to address the issue to avoid potential emissions problems.
Q: Will a loose gas cap cause a P147B code?
A: A loose gas cap can cause similar codes, but P147B specifically relates to the pressure sensor or switch.
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Fitment Required · Vehicle-fitment part
Relevant for some EVAP leak codes where the fuel cap or sealing surface is part of the problem.
Some EVAP leak faults involve the fuel cap or its sealing surface.
Fuel caps vary by vehicle and should be matched to the exact application.
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Fitment Required · Vehicle-fitment part
Relevant when EVAP diagnosis points toward purge-flow or purge-control faults.
EVAP diagnosis often includes purge-flow and valve-control faults.
Confirm the failed valve and exact fitment before buying parts.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.