P0456 - Evaporative Emission System Leak Detected (very small leak)
 

Howdy All,

Forgive me is this is already posted some where. I'm getting the above code on my 2011 Q5 2.0T with 58k Miles. Any thoughts/suggestions?

I don't know if its related to the issue "P0343 - Camshaft Position Sensor "A" Circuit High Bank 1 or Single Sensor" code I'm neglecting to fix until I find time to really tear into the engine to replace this sensor.

Thoughts?

We had a recurrent P0456 error on our 2010 3.2 Q5 within the 1st year we owned it. Dealer and corporate (they sent an engineer from Germany) tried fixing it ~6 times and probably replaced the entire evap system. They never could find the root cause and ended up replacing the vehicle with a new one.

I think they progressively replaced:
gas cap (2x)
gas tank & filler
evap canister
evap solenoid(s)?
evap lines

Good luck to you.

I have to say, the 0456 code is almost always due to a loose gas cap, failing gas cap, or refueling with the engine running (awry's experience not withstanding!). It's the most minor level OBD EVAP leak code. If you've verified the cap is tight and/or have replaced it, the code may hang around for quite a few cold start--> warmup cycles before it turns off the MIL light. If you clear the code, it should obviously stay away.

2011 Q5 P0456 small leak
 

I've been dealing with this for a couple of months. I have a Ross-Tech vag-com software/tool to help. I did all the recommended things, gas cap, purge valve and then this morning opened up the bottom of the car, below the passengers seat driver's side. This is the location of the charcoal canister - the first hose I pushed in gave a very satisficing
https://cimg2.ibsrv.net/gimg/www.aud...cd04ecd713.jpg
https://cimg3.ibsrv.net/gimg/www.aud...d1553cf4fb.jpg


"click" - rescanned and all is good. Now to get it to emissions and see if they feel that way too. :-) I'm posting the pictures, because I could not find any info online on the canister's location. Hope this might help someone who is dealing with the same code.

The Evap codes have nothing to-do with the camshaft codes.

Assuming the gas cap is tight, and its gasket is OK, then it is a common issue with the B8 era of Audi vehicles, to have "Small Leak Evap" codes pop up as these cars get older, and the fuel system vent seals get a tiny bit leaky, or the diagnostic sensor used for leak detection drifts off of calibration. My 2010 S4 began to do this, and my 2015 Q3 just started doing this. I get a "Small Evap Leak" code maybe once or twice a year.

2013 Q5 premium plus 2.0L threw P0456 code last month. I replaced gas cap in Nov. Since the beginning of Nov, it has been throwing this code 3 times. It sounds expensive to really fix this code :). Any good advise please?

Did you get a genuine VAG gas cap? My experience with the aftermarket units is that they don't vent properly and cause that code.

Oh I did not get a genuine VAG gas cap. I bought an after market one on Amazon :). Let me look for a genuine VAG gas cap. Is there a good place to buy that? Thank you!

My non-working aftermarket one was from Amazon too, $12, and returned.

Audi, FCPEuro, ECS, etc sell the genuine cap for $50-$80 or so.

Thank you for the website! I'll return mine and get a genuine one.