Disappearing P3009

I have not had this problem again since the last report. And I'm more confident that it was (is?) just an intermittent weirdness from high interior moisture. (My half-baked "theory" but the only one I have). So the rest of the half-baked theory story...

I never found any actual water leaks to the interior. But what I did eventually figure out is that maybe I just need to keep the damned car clean? The "gutter" area around the trunk seal is pretty big and deep, which is cool b/c it can channel a lot of water. But it also likes to collect debris.

When the COVID crap went down, it was easy for me to shift to remote work and stay home. So I did. I live on a heavily wooded lot, and not using the car very much (and even then rarely going into the trunk in any case) the car got pretty grungy sitting around under the trees. So one day I decided to give it a good cleaning. That trunk gutter was stuffed full of crap - shards of tree bark, twigs. leaves. It makes like a big sponge. It wasn't "leaking" to the point that my trunk was wet. But it was a route for moisture to make it inside.

But I still have to wait until next summer too. By my half-baked theory, I need both hot and humid weather and heavy rain. I'm in Central VA, so we get some fat rain once in a while through fall and winter. But no hot and humid weather until summer. If I think of it I'll update.

Another "seasonal affliction" is my P0420 (cat below efficiency). I've had the car like 4 years. Every winter it starts throwing that code, and then only during interstate driving (60-70+ mph). Come spring I can clear it and it won't come back until winter... Or I can not bother to clear it and it clears on its own. Or it can be winter and I stay off the interstate driving and stays away. There's some half-baked theory that could go into that too - cold weather fuel mixes are richer. So a cat nearing it's inability to do its work might do that. But seriously? Not for 4 years in a row. If it's on its way out, then it's on its way out.

I guess I'm just saying that I do trust the computers and their error monitoring...but with a grain of salt.

In any case, @Stock808, be very careful about equating your P3009 issue with mine. If you have a car just plain throwing a triangle and P3009, then that's not the same thing. And it's not something to take lightly. Mine would randomly pop up and then magically just ... poof ... disappear and not come back - for like a year. But I haven't seen it now for like 6 mos. I'll see what happens in 6 mos. In the meantime, I've now only got a "temporary" P0420 set...because it's wintertime. And I've been on the interstates lately.

 

Just time for the yearly report. We had a very dry spring and early summer. Then a huge round of rain followed by high humidity. Then I got the P3009 again. The last time was last summer at my lat report.

No good details. Still no signs of leaks to the interior. Soon after all the rain and the code I had to go out of town for a week so the car wasn't driven (left the 12V disconnected). During that time there was high humidity and daily thunderstorms. Came home yesterday and we hit a period of lower humidity today. I aired out the car, drove it today (ample time for code setting) and got nothing.

That's it. The yearly appearing/disappearing P3009. I put a tub of "Damp Rid" in the trunk. Probably means nothing, but can't hurt anything. I have the random P3009 in the summer and the less-random P0420 in the winter (but only on the highway).

So just an update if it helps anyone, Tho' IDK why it would since it answers no questions.