P0496: EVAP Flow During Non-Purge Condition

Most modern vehicles have an on-board diagnostic system in place to make it easier to diagnose problems with a vehicle. Using a special tool, you can get a specific error code from the vehicle, which should tell you exactly what is wrong. At least, this is the theory behind the system. In practice, it is a little more difficult to make repairs based on the error code. For example, if you experience an OBD-II scanner error code P0496 problem, that means there is flow in the EVAP system at the wrong time. Do you know what that means? If not, then having the code does little to help you. It does help your mechanic, however. If you do not want to send your car to the mechanic right away, then this guide will help you take a crack at fixing things first.

What Does P0496 Mean?

First, you need to understand your car’s EVAP system. Gasoline produces hazardous fumes. You probably get the slightest hint of it when you fill your car with gas, and you have certainly smelt the strong odor if you have ever been exposed to uncovered gasoline. These fumes can only hurt you if you are exposed to them for a long time, but it is important for your car to contain these fumes correctly so they are not released into the atmosphere, because there are a lot of cars on the road. This is what the EVAP system does and it does it using vacuums. If the car detects that there is flow in the EVAP system when there is not supposed to, it means there is likely a leak in the system that is releasing this hazardous fumes.

What are the Symptoms of P0496?

There are very few symptoms associated with this error code. The car will illuminate the check engine light, and that will likely be it. It is possible that the car may have a hard time starting. Even if this symptom does show itself, it is usually subtle enough that it is easy to miss. You should not rely on any outward symptoms, and instead use the error code and check engine light to know when something is wrong with your EVAP system.

What is the Danger of Ignoring it?

You are not in any physical danger if your EVAP system is malfunctioning. You are, however, contributing to the worsening environmental crisis more than a typical car is supposed to. Your car will also likely not pass a smog check if this is left unchecked. Even if the fumes leak into the interior of the car, you should be completely safe because they are not concentrated enough to hurt you. As with any issue, the cause of a malfunctioning EVAP system may cause other problems. There is no way to know when another issue will crop up or how severe it will be. A malfunctioning EVAP system may be caused by:

  • Faulty vents or purge process
  • Blocked or disconnected canister
  • Mechanical failure
  • Electrical failure

How to Fix P0496

You are probably most interested in knowing how do I fix trouble code P0496? This issue is most commonly caused by a faulty purge solenoid valve. You can only be sure if you have an advance scanning tool, however. You can check the fuel tank pressure and compare it to your car’s specified range. If it is too high, then you should replace the purge solenoid valve. If this is not the cause of the error code, then you should visually examine every part of the EVAP system. If nothing mechanical seems to be wrong, then it is likely the sensor malfunctioning or a short circuit. Doing electrical work is more difficult and dangerous, but you could likely change the sensor relatively easily.

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