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 your car that controls how gas fumes are released. It's like a valve that should open and close, but it's stuck open.
The EVAP system captures fuel vapors from the gas tank and prevents them from escaping into the atmosphere. The purge control valve controls the flow of these vapors into the engine to be burned. If this valve is stuck open, it can cause issues with the vehicle's emissions system.
The P04AE code indicates that the Engine Control Module (ECM) has detected a malfunction in the EVAP system's purge control valve B. This valve is responsible for regulating the flow of fuel vapors from the charcoal canister to the intake manifold. A stuck open valve can lead to an imbalance in the air-fuel mixture, affecting engine performance and increasing emissions.
• Check Engine Light is on
• Poor fuel economy
• Rough idling or engine performance issues
• Faulty purge control valve
• Damaged or disconnected vacuum hoses
• Wiring issues in the purge valve circuit
EVAP: Evaporative Emission Control System
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code
• Inspect the purge control valve and related hoses for damage
• Check the electrical connections and wiring for faults
• Replace the faulty purge control valve
• Repair or replace damaged vacuum hoses
• Fix any wiring issues in the valve circuit
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $250
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly inspect and maintain the EVAP system
• Keep the gas cap tightly closed
• Use high-quality fuel
Emissions Control Issue
• Get the issue diagnosed and repaired promptly to avoid further damage
• Monitor fuel economy and engine performance for signs of improvement
Check your vehicle's warranty to see if emissions components are covered.
The P04AE code has been associated with issues in the EVAP system in various models, often linked to faulty purge valves.
Moderate – While not immediately critical, addressing this issue can prevent further emissions problems and improve fuel efficiency.
Ignoring emissions-related issues can lead to increased pollution and may violate environmental regulations.
• Engine at operating temperature
• Vehicle in a safe, ventilated area
The purge control valve is typically located near the engine, connected to the intake manifold and the EVAP canister.
Q: What happens if I ignore the P04AE code?
A: Ignoring this code can lead to increased emissions and potential damage to other components in the EVAP system.
Q: Can I drive with a P04AE code?
A: While the car may still be drivable, it's best to address the issue to avoid long-term damage and ensure compliance with emissions standards.
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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.