Error P0496 – how to fix?

P0496 OBD-II trouble code: EVAP flow at no purge

P0496 Code Definition

This is a generic code and applies to all vehicle brands, however it appears to be more common on GM vehicles. This means there is a problem with the purge flow in the evaporation system. People with Mazda, Kia, Hyundai, Honda and Acura cars will notice that the code description is slightly different. This is called high EVAP blowdown flow, but it means the same thing.

What does the code P0496 mean

This code indicates that there is an undesirable amount of vacuum flow in the intake system in the EVAP system. When the EVAP system vacuum is higher than the default value, it may cause a code to set.

What causes the code P0496?

There are many potential causes for the P0496 code to appear, including the following:

• Defective solenoid / overload or vent valve.
• Clogged EVAP canister
• Fuel pressure sensor / VEHAP failure
• Faulty electrical connections
• Defective fuel tank vent valve
• Defective deaeration coil
• There may be other causes in some vehicles. In Hyundai cars, the cause may be a leak in the EVAP seals, while in Kia and Mazda cars, the cause may be a damaged desludging flow sensor.

What are the symptoms of the P0496 code?

Some of the most common symptoms of the P0496 OBD-II code are the lighting of the malfunction indicator on the vehicle. However, there are probably no other symptoms that would be noticeable to the driver. In some cases, there may be problems starting the vehicle and the engine may run “rich”, which can cause problems with the catalytic converter and other engine components.

How can a mechanic diagnose the P0496 code?

When a mechanic needs to diagnose a vehicle, he uses an OBD-II scanner connected to the vehicle’s computer. The computer stores any problems with the vehicle in the form of fault codes. When they see P0496, they know the vehicle has a potential problem with EVAP flow under non-purge conditions. To make sure the code is accurate and has not been mis-activated, they reset the code and start the vehicle. If the code shows up again, they know it’s a problem they need to fix.

The most common errors when diagnosing the P0496 code

One of the most common mistakes made in vehicle diagnostics is the belief that the problem is always with components of the evaporative emission control system. Mechanics can replace them when there is actually a vacuum leak. In some cases it can be as simple as an improperly tightened fuel cap. It’s important to check for smaller, simpler potential solutions first, and then work on larger potential replacements and repairs.

How serious is the P0496 code?

While there are few signs and symptoms of this type of problem on your vehicle, it is still important to fix the problem as soon as you are aware of it.

What repairs can fix the code P0496?

The following are some of the possible repairs that can be performed to remove the P0496 code.

1. Use the scanning tool to determine the code.
2. Reset the code and start the vehicle to see if the problem recurs.
3. Check the fuel cap
4. Check the purge solenoid valve, which may need to be replaced.
5. Repair or replace the fuel tank pressure sensor.

Additional notes on the consideration of the P0496 code

If this or other problems occur on your vehicle, do not ignore them. It’s best to take them to a mechanic for proper treatment and to make sure the vehicle is in good condition. Ignoring such a problem can eventually lead to other problems with your car or truck.