Toyota decided to use crappy foam filters for the secondary air injection systems, for 2012 to 2015 Tacomas. The side effect of this is how the foam filter degrades. The foam filter can disintegrate and be sucked into your intake, causing potential damage.
Some Tacomas are affected by a recall by Toyota as well. You can enter your VIN here to check for recalls.
I’ll show you how to remove the factory filter, and replace it with an aftermarket filter. The pictures below are from my 2014 Toyota Tacoma, 4 cylinders.
What is the secondary air injection system?
The secondary air injection system is for emissions control as it sucks more air in. It only runs at startup and shutdown
It also helps with catalytic converter life. It purges the exhaust fuels out of the exhaust on shutdown and pushes clean air in during startup so they don’t get clogged by moisture and/or an over-rich startup mixture.
The easiest fix is to remove the foam filter and replace the OEM filter with an aftermarket filter. The filter we need has an inner diameter of 1″.
There is a drop-in solution for replacing the filter as well, you can find these filters on Amazon or eBay:
Open your hood and find the SAIS on the passenger side, near the airbox.
Remove the plastic shroud by releasing the clips. You can see a clip, closest to that electrical plug. There is an additional clip on the shroud on the backside. Release the clips (flathead screwdriver or needlenose pliers) and pull straight up.
With the shroud off, you’ll have to use a T25 Torx bit to remove the plastic cover.
Once the cover has been taken off, you can see the chunk of foam stuffed in the intake system.
Take out the foam and pull off the plastic filter cap.
Attach your new filter, tighten it snugly, and put everything back together.
This is an incredibly easy mod to do and protect your truck in the event of the foam failing. I think it would be rare for the foam to degrade, but it can happen. Toyota has issued recalls for certain Tacomas, so they are aware it is a problem. This fix gives me peace of mind when I’m out roaming the backcountry.
While you’re there, you might as well replace your engine air filter too!