P1457 on Honda is a complex code to diagnose and fix due to the complexity of the components involved. It is a common problem in Honda Civic, Accord, Odyssey, and CR-V vehicles that may require a professional technician for a more positive outcome.
The OBD2 code is related to issues in the EVAP (Evaporative Emissions Control System). The leading causes of the PCM storing the above code include:
- A faulty EVAP charcoal canister vent shut valve.
- Defective or damaged vacuum line to the canister.
- A malfunctioning two-way Bypass valve.
The P1457 code can be fixed with straightforward procedures, but the repair person must be well experienced in using the tools needed. Moreover, the repair person must be familiar with thorough maintenance procedures for an easier and faster repair.
- 1 P1457 Honda: What does it mean?
- 2 Symptoms of code P1457 on Honda
- 3 What causes the P1457 Honda
- 4 How to diagnose and fix the code P1457 on your Honda
- 5 Other codes related to code P1457
- 6 Tips to avoid code P1457 in the future
- 7 Final Thoughts
P1457 Honda: What does it mean?
The P1457 Honda OBD2 diagnostic trouble code is defined as “Evaporative Emissions (EVAP) control system leakage (EVAP Canister system) EVAP.”
P1457 is a manufacturer-specific code, meaning that it does not apply to all vehicle models. The code applies to specific vehicles such as Honda, Ford, BMW, Mercedes, Porsche, Volkswagen, and GM. Its meaning, definition, and fix across all these vehicle models might also be different.
P1457 Honda, P1457 Acura, and P1457 Ford expressly point to an EVAP canister and vacuum retention issue.
Meaning of P1457 on Honda
The P1457 code is stored by the ECM when a fault gets detected in the EVAP system. The Evaporative emissions control system (EVAP) defect may prevent it from either maintaining or pulling a vacuum in the fuel tank.
Components that make up the EVAP system include; fuel tank, fuel filler cap, wiring and connectors, vacuum lines, and fuel lines. Other elements in the system include; control solenoids, purge valve, vent valve, charcoal canister, and pressure sensors.
The system helps to trap fuel vapors before they can be transferred into the surrounding atmosphere. It does this by storing the fuel vapors in the canister. The stored vapors are then directed into the engine through vacuum lines to get combusted as a composition of the air and fuel mixture.
The process begins when fresh air is directed into the system through the vent shut valve to assist in disposing of vapors from the canister.
The ECM/PCM does successful self-tests on the EVAP when the fuel tank is 25% and 85% full. The test gets done by closing the vent control valve until the engine vacuum has developed enough vacuum by sucking fuel vapors into the engine via the purge valve. If a sufficient vacuum gets created, the ECM shuts the purge control valve leaving the system sealed.
The PCM will then search for leaks to determine if the vacuum is maintained for a needed period. If the time is achieved, the PCM will conclude that no leaks exist, thereby opening the vent valve again till the following self-test is deployed.
There should be no leaks for a well-functioning EVAP system. If leaks exist in the fuel cap, charcoal canister, or vacuum lines, the engine will be unable to create or maintain the self-test vacuum. If this happens, the P1457 DTC will be stored by the PCM, and the check engine light will turn on.
Symptoms of code P1457 on Honda
- An illuminated Check engine Light (CEL)/ Service Engine Soon Warning.
- A stored P1457 OBD 2 trouble code.
- Rough idling and engine stalling if a large vacuum leak exists.
- The vehicle fails an emissions test at least twice.
- Fuel smell and odors will be noticeable if a leak exists.
What causes the P1457 Honda
- A damaged vacuum line to the charcoal canister.
- Stuck or corroded EVAP vent valve.
- Burnt or corroded wiring and connectors.
- Faulty and open circuits.
- Bad fuel tank pressure sensor in case of other fuel tank pressure sensor-related codes exist.
- Malfunctioning purge valve in case other purge valve-related codes exist.
- Faulty canister fuel cap.
- Broken or malfunctioning EVAP charcoal canister.
How to diagnose and fix the code P1457 on your Honda
- The first tip for any auto repair requires you to look for any technical service bulletins (TSB) for your vehicle model relating to the P1457 code. TSBs will save you time and money since they show the verified solutions to the code.
- Get your vehicle manual for any repair suggestions and follow the recommended steps for fixing the P1457 code issues. Check for these two (the TSBs and vehicle manual) before embarking on any generic diagnosing and fixing process.
- You will need a few tools for this diagnosis:
OBD2 scan tool/ OEM equivalent scanner with control functions.
- Repair manual with a pressure-to-resistance chart.
- Digital multimeter.
- Vacuum pump.
- Smoke machine.
4. The diagnosis and fix will be more straightforward if the vehicle is placed on a hoist or lift to access the components.
Record all the stored OBD2 diagnostic trouble codes using the scan tool. Other codes that may be present should be fixed first, especially if they relate to the EVAP or fuel system.
Clear all the codes after fixing the other stored codes, in case there were any. Test drive the vehicle for at least one complete drive cycle and rescan to see if any codes return. Proceed to the next step if the P1457 code returns.
Use the Honda vehicle manual to locate the EVAP components and their associated wiring, connectors, fuel lines, and vacuum lines. Visually inspect all the lines, wiring, connectors, and the various EVAP components for damages, cracks, or corrosions.
Remove and shake the charcoal canister for any signs of charcoal charge disintegration. Replace it if there is any sign of charcoal dust in the EVAP system. You can also test the charcoal canister for airflow issues, airflow should only take place away from the vent valve.
Replace all the affected components with appropriate replacement parts to avoid leakages. Corrosion on the elements, especially the charcoal canister, can lead to faults in the valves, causing them to get stuck due to corrosion or leaks.
Clear all the stored codes after fixing the issues. Perform a test drive for at least one complete drive cycle to see if the code returns. Proceed to the next step if the P1457 code returns.
Visually inspect all the wiring and connections around the EVAP system. Check for damages, shorts, burns, disconnections, and corrosions.
Perform the necessary repairs on the wiring and connectors. The best course of action is to replace the wiring and connectors.
If the code is returned, check for any poor electrical connection on all the interconnecting wiring. You will perform ground, resistance, and continuity checks on these wiring. This is the step where you will have to use the digital multimeter. Disassemble the EVAP system for individual component inspection.
The vehicle manual has a specified value for the input voltage, which should be noted while performing this check.
Use the vehicle manual on how to perform the resistance, ground, and continuity checks for your car specifically. Always remember to disconnect the EVAP system from the PCM during resistance and continuity checks. This is to prevent the controller from being damaged by the process.
Perform the needed repairs if any diversions are found. Recheck the input voltage again to see if the repairs solved the issue. Go ahead and proceed to compare the control valve resistance to the one on the manual and replace the valve if the values do not match.
In case the P1457 code persists, then the issue may involve leaks in the vacuum line. This is the step where you will have to perform a smoke test of the entire EVAP system. Reassemble the EVAP system and ensure that the vent valve is closed and the purge valve is open.
Connect the smoke machine to where the vacuum line meets the inlet manifold. Proceed to command the purge valve open using the scan tool. This allows the smoke to fill the entire EVAP system. Let the smoke settle in the system for about 60 seconds to several minutes.
Look out for any smoke that may appear from pinholes in the vacuum lines. The cap and cables need to get replaced if you notice smoke escaping from the vacuum lines or the fuel filler cap.
You will need to use the vacuum pump if the smoke machine doesn’t detect any leaks. This is because a smoke test can’t always reveal a leak.
Connect the vacuum pump to the system and draw a vacuum. Make sure the purge valve is open, and the vent valve is closed. If everything is working optimally, the vacuum will hold for a couple of minutes; otherwise, the faulty part will need to be replaced.
Replace the vacuum lines, valves, or filler cap depending on where the smoke escaped or where the vacuum can’t get held.
These steps should help you get rid of the P1457 code. If not, then the code may be a result of another fault. You will need to look for that fault and fix it before re-running the above steps.
In case the issue persists, you will have to give it a considerable amount of time to worsen. This will enable you to diagnose the code accurately and fix it with absolute certainty.
- P1456 – Evaporative Emissions Control System Leakage Fuel Tank
Tips to avoid code P1457 in the future
The primary tip that will help you avoid getting the P1457 code in the future is to take care of and maintain the EVAP charcoal canister, the associated valves, and vacuum lines. Avoid muddy and dusty roads or do a regular cleaning and maintenance procedure to remove any deposits. Corrosions and leaks can result in damage to the canister vent valve, making it stuck.
The P1457 OBD2 code possesses no drivability concerns since it has no relation to the engine’s performance. However, leaks in the fuel system may eventually result in other issues that will cause drivability concerns.
Some of the potential resultant symptoms may include poor gas mileage and engine misfires. The prudent and most recommended course of action is to fix the P1457 OBD2 diagnostic trouble code as soon as you can.