jablo

Hey all, my new to me 981 started throwing a CEL 3 days after picking it up saying something to the effect of "Check engine, but okay to drive on". I read the code after getting home as P0456.

Now the previous owner did tell me he had this code pop up a few months ago, replaced the gas cap and hadn't had it return since then. I'm guessing the gas cap was not the issue so now I'm trying to figure out what to do. Are there any easy things to check/try before just dropping it off?

The one thing I will add is that on my first gas stop I accidentally overfilled the tank and some fuel came out the overflow (Yes I know I shouldn't do this, it took less fuel than I expected and I thought it must have clicked off erroneously). Not sure if this points a finger at anything, but it's the only fuel system related event since picking up the car.
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maschinetheist

Could it be the fuel vapor charcoal canister/filter? If you overfilled, it could've gotten wet via the vent tube. I believe that it should be accessible through the wheel well where the fuel filler/gas cap is. I'd clear the code, wipe any fuel around the fuel filler/gas cap, and see if it comes back up.

jablo

Could be. It looks like it might actually just be right next to the air compressor under the front service panel, but I'm not sure if I'm interpreting the service doc correctly. I'll see if I can get at it and see anything amiss

Kitc2246

Check you car for the recall associated with the gas evaporative system.

jablo

Hmm, nothing from the vin lookup, but that's interesting. Do you have the details of the recall or a TSB number or similar?