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Check Engine Light EVAP Flow During Non-Purge Condition - Code P0496

Created on: 2020-06-18

Watch this video to learn how to diagnose and fix a check engine code P0496

So you use a code reader, you scan your vehicle, you had a check engine light, you have a P0496 which is an EVAP code, what do you do?

Now whenever you have an EVAP code, it's always a good idea to check the gas cap. Regardless of what the code is, just make sure because it could be loose and cause your issues. Pull the gas cap off and just take a look at the seal. It looks good. All right, we can move on. So what this code's actual description is flow during non-purge for the EVAP system. Now, what does that mean? That means that the vacuum from the engine goes through this purge valve right here and the computer commands this on and off. And that's gonna send vacuum back to the gas tank and to the EVAP canister. It has to do with the emission system. Now what the code is saying is that this valve right here isn't working properly. So what this valve does when the computer is not commanding it on or not commanding any power or ground to the valve itself, it is normally closed. So you're going to have engine vacuum in a hose going to the valve. And then after the valve, there should be no vacuum. Okay. So what you could do to check this out is take this line off, the line that goes to the back of the vehicle, and then disconnect the connector right here. So with those two disconnected, this should always be closed. So if you started the engine and you felt vacuum here, you can either use a vacuum gauge or you can even use your finger and see if there's any vacuum here while the engine's running, then this valve is stuck open and it needs to be replaced.

Now you can always take this valve out. This one, I just need a screwdriver just to pry the bracket out a little bit then I can slide this out completely and out of the way. I can take this hose off right here and there it is. Another way to test this, if you didn't want to test this while the engine is running is you can take a hose and you could actually try to blow through this and see if you can actually blow through it either direction. You shouldn't be able to, or you can use a vacuum pump. And with this all hooked up, you can put a vacuum on it. And as you can see, ours is leaking. Just make sure your fittings are good, everything looks good, and your vacuum gauge is good, but this should not do this, this should be solid all the time. And it leaks so this needs to be replaced. So you can take the new purge valve, slide it in position. Every vehicle might be a little bit different, but normally the purge valves are somewhere close to the intake and you'll see an electrical connector. Normally, the connector is only two wires. It's just an on and offs basically. There'll be a power and ground there, and unless you had power and ground stuck on all the time, this should always be closed unless the computer's commanding it on. Lock it back in, hook up the line that goes back to the vapor canister and slide the connector back in, lock it in place.

All right. At this point, you can clear that check engine light, drive the vehicle, you should be good to go. If you have a more powerful scan tool, you should be able to test the system and see if it's working properly. If you enjoyed this video, please subscribe to our channel. Make sure you ring that bell, turn on all notifications so you don't miss any of our videos.

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