Evap codes after replacing air filter...

Alright I'm getting sick of seeing these codes, it's time to ask the community here for advice, lol.

I have a 2017 4x4 TRDOR with ~63k miles. For a while now I've been running a Volant CAI. As a side note, don't buy the Volant CAI, it has fitment issues and rattles due to poor fastening. There are better options out there.. I've fixed the problems though with a little cutting and reinforcement in areas and it has been fine.

The Volant came with its own cone filter, which felt very cheap. But I ran with it for several thousand miles, no issues.

A couple of months ago, I replaced the Volant cone filter with a K&N cone so I could clean it when necessary. I dropped it right in to the Volant CAI box and off I went.

Not shortly after, I began throwing evap error codes. Always these two.

P0441 - Evaporative Emission Control System Incorrect Purge Flow
P2420 - Evaporative Emission System Switching Valve Control Circuit High



I read that this can be caused by a dirty MAF sensor so I cleaned it. It kept throwing these codes. I cleaned the MAF sensor again. Then I took out the K&N and put the old filter back in. Still threw codes. I washed and re-oiled the K&N, cleaned the MAF sensor a third time.. Still codes.

There are articles out there about how the K&N absolutely positively will not foul up a MAF sensor, but that seems to be almost exactly what has happened in my case.

The truck drives perfectly fine, MPGs are still average, so whenever I see the CEL I just clear it with my OBD scanner (probably not the best thing to get in the habit of, but I digress).

The CEL stays off from a week or so, through a dozen driving cycles at least, but it always comes back.

I'm ready to get this problem fixed, but I'm hoping to avoid the dealer for obvious reasons.

Any ideas? Should I try replacing the MAF?

Also, if you want to flame me for modding my truck, feel free.

TIA!

 

Yeah your looking in the wrong place with the MAF.
P0441 is a rare one for a Toyota... probably a bad vacuum switch or a leak in the evap system.
P2420 faulty vacuum pump module, poor circuit connection.
If there is no leak in the system you got a bad connection between the ECM and the module. Loose wire, broken wire or the green puss. Probably damaged a wire or connector or hose while fucking around with the intake trying to make it fit better.

 

Interesting, thanks for the feedback. I will do a cross check of all wiring. I don't know where the vacuum pump module is, but if it's on that side you might be right. I'll do some research.