P1456 is a very common trouble code in vehicles made by Honda. It is a Honda specific code, which means that it has the same meaning in any vehicle manufactured by Honda (including Acura). P1456 is typically caused by a faulty or loose gas cap, although there are other issues that can cause it as well. We’ll take a look at those directly below.
P1456 Symptoms Honda Avancier
Symptoms of P1456 typically include the smell of fuel, and P1456. It is telling you the the Avancier’s diagnostic computer believes that the EVAP leakage is coming from the fuel tank, which is why starting with the fuel cap is a good idea.
Honda Avancier P1456 Causes
As stated above, the most common cause of P1456 is either a faulty, loose, or missing fuel cap. If that’s not it, it’ll usually be the EVAP system. Certainly every model year is going to have its own set of circumstances, but these are the most likely causes of P1456 in the Honda Avancier in general.
- Fuel Cap– The fuel cap is the best place to start diagnosing P1456. It’s the most likely reason that the code has been thrown, as well as the least expensive and easiest to access part to replace. Here is a great video on how a gas cap can cause trouble codes. When they have gone bad, gas caps typically will fail to tighten. You may also be getting a message that says to tighten the gas cap. Here’s a good article on the symptoms of a bad gas cap.
- Fuel filler neck/input– It is certainly a good idea to take a look at the fuel filler neck and see if there is any damage or debris that could be keeping the fuel cap from making a tight seal. There’s an O-Ring that will connect the fuel filler neck to the gas tank. If it has dried out or broken, the fuel tank will no longer be able to pressurize and P1456 will be thrown.
- EVAP System– The Evaporative Emissions Control System carries fuel vapor from the fuel tank to the intake manifold. If it develops a leak, it’ll often also throw codes such as P0455, P0456, or P0457, These codes indicate that there is an EVAP leak. The only difference in them is they each indicate a different size leak. When the EVAP system is leaking, it can throw P1456 because it would depressurize the fuel tank much in the same way as a missing gas cap would. Here’s a video on how to test the EVAP vent canister Valve with P1456 in a Honda made vehicle.
Conclusion
Most of the time, replacing the fuel cap will clear P1456. It may take the vehicle awhile to reset the code. Make sure to drive it a little before inspecting the fuel filler neck or checking the EVAP system. If there’s anything you’d like to add, please leave a comment below. Good luck!