You need to read this if you own a Honda, and the check engine light is on with a P2422 trouble code. P2422 refers to a stuck shut vent valve on an EVAP canister in the evaporative emissions system.
In this case, the EVAP vent valve is stuck closed, causing the P2422 diagnostic trouble code. The EVAP system reduces harmful pollutants emitted by the combustion process.
The EVAP vent valve allows fuel vapors to enter the engine. Engine vent valves regulate the amount of fuel vapor allowed to enter.
A stuck EVAP vent valve prevents fuel vapors from entering the engine by preventing them from flowing through it. However, it is not always the case that vent valves are defective.
P2422 Honda Definition: Evaporative Emission System Vent Valve Stuck Closed
Fuel vapors from the fuel tank are captured by the evaporative control (EVAP) system, which sends them to the vehicle’s intake to be burned.
By opening the vent valve, fresh air enters the EVAP system, preventing it from being under constant vacuum. A code P2422 is set by the engine control module (PCM) when EVAP vents when it shouldn’t.
During the operation of the vent valve control circuit, a voltage signal is sent to the powertrain control module (PCM). This voltage signal carries pressure and flow information related to the EVAP system.
P2422 diagnostic trouble code is stored in the PCM when this voltage signal does not meet the manufacturer’s predetermined voltage specifications, which will cause the Check Engine Light to illuminate.
Learn More About OBD Error Code P2422
Toxic contaminants are not released into the environment due to the EVAP system, which decreases the number of toxic contaminants produced by the engine burning process.
A vent valve in the EVAP system allows fuel vapors to enter the engine. In an engine, fuel vapors are controlled by the vent valve.
By jamming the EVAP vent valve closed, fuel vapors will not be allowed to enter the engine through the vent valve.
The vent valve control circuit sends an electrical signal to the powertrain control module (PCM). Signals such as these provide information about EVAP system stress and course.
The PCM will supply the P2422 diagnostic error code, and the Check Engine Light will illuminate if this voltage signal fails to match the advanced decision to have the manufacturer set up the voltage.
Code P2422 Honda: What Are The Possible Causes?
Essentially, the code indicates that when the vent valve is open, the ECM is not seeing a change in pressure or vacuum. The following problems commonly trigger the P2422 code:
- The PCM is faulty
- Corroded or damaged EVAP connectors
- Damaged, broken, or shorted EVAP wires
- Damaged, loose, or broken fuel vapor hoses
- Damaged, loose, or broken vacuum hoses
- Fuel cap that is loose or missing
- Flow sensor malfunction
- Solenoid faulty in purge control
- The pressure sensor is faulty
- A faulty solenoid controls the vent valve
- The vent valve is faulty
What Is A Mechanic’s Process For Diagnosing A P2422 Code?
- Using the OBD-II scanner, all trouble codes and freeze frame data from the PCM are collected.
- Examines the wiring of the EVAP system for breaks, frays, corrosion, and shorts.
- Verifies that no bent pins, broken plastic, or corrosion exist on the EVAP system connectors.
- Replaces or repairs damaged EVAP wires and connectors.
- Tests the fuel cap with a fuel cap tester to ensure it is properly affixed to the fuel inlet.
- Checks if the P2422 trouble code comes back after clearing all trouble codes.
- Verifies that the EVAP system vacuum lines and hoses are not damaged or connected loosely if the P2422 trouble code returns.
- Inspects and repairs damaged or loose vacuum lines and hoses.
- Performs a test drive to determine if the P2422 trouble code has been cleared.
- If the P2422 trouble code does come back, check the charcoal canister for damage.
- Checks the leak detection pump according to the manufacturer’s instructions.
- Performs EVAP controller and component testing with a scan tool.
- OBD-II scanners should be used to diagnose any additional EVAP system diagnostic trouble codes stored by the PCM.
For the P2422 trouble code to be properly diagnosed and fixed, it will take time and attention to detail. An EVAP control system smoke machine will be useful in finding vacuum leaks.
Diagnosing The P2422 Error Code: Common Mistakes
EVAP leak detection pumps are not tested for proper operation before extensive amounts of time are spent on finding vacuum leaks.
The leaks in the EVAP system are not discovered and repaired before the parts are replaced. Sometimes vacuum leaks result in P2422 trouble codes, and EVAP components need not be replaced.
Symptoms Of The P2422 Error Code:
Having a clear understanding of the symptoms of a problem will make it easier for you to solve the problem. Here are some of the main symptoms associated with OBD Code P2422:
- There is a decline in fuel efficiency
- Rich or lean exhaust
- There is excessively low fuel pressure
- Not a single symptom can be found
- There is an engine check light on
- PCM-stored diagnostic trouble codes associated with the EVAP system
ECUs make an effort to raise engine temperature, which causes the engine oil to become diluted. Some vehicles increase fuel injection timing vaguely after the top center to have a higher exhaust temperature after burning a small amount of fuel.
It is unlikely that much of this fuel will reach the crankcase. The oil will have a short service life as the ECU determines if the DPF needs to be reprocessed.
How To Fix OBD Code P2422?
When you aren’t equipped with the right tools and information, troubleshooting a P2422 code can be frustrating and confusing. You may want to leave the DIY task to the professionals if you are not confident in your DIY skills.
However, ensure you have the right manuals before attempting any repairs if you think you have the automotive know-how. When the vent valve becomes stuck open or doesn’t work, this is the most common problem.
A vent valve is replaced, and the structure of the vent valve is changed as part of the adjustment. Filling up the gas tank can be challenging if the vent valve is blocked.
Is The Honda P2422 Code Serious?
Diagnosed trouble codes are usually considered serious if they affect performance or drivability. However, neither drivability nor performance issues are associated with the P2422 diagnostic trouble code.
Due to this, it is not considered serious, but should be addressed as soon as possible. An engine component may be damaged if diagnostic trouble codes remain in the PCM for long without being addressed.
In the unlikely event that you don’t reset the check engine light, the engine will take some time to clear it. This is because the vehicle must test its EVAP system before clearing the check engine light.
The dealer has the diagnostic equipment for finding the problem without replacing parts, so I would recommend having the dealer troubleshoot it.