Secondary Air Injection Valve Replacement write up. Check Engine Light with P2441 code

2008 Tundra 5.7 Limited CrewMax 158,121 miles. Purchased by me in 2017.

So I bought a base model 2012 hatchback Subaru Impreza to help offset some of these crazy gas prices. My goal is to drive the Tundra a few times a month for fun or when I need to pull the boat or whatever. I miss driving her, but the savings on gas are paying for the car. It's basically a free car. Anyway, I hate letting vehicles sit because I know it always seems to cause issues.

Well, I got into the Tundra to move it the other day and the Check Engine light was on. First time in 5 years I've seen any light other than tire pressure monitoring and maintenance. I ran the OBD2 scanner and the got the dreaded, but all too common, P2441 code (Secondary Air Injection System switching valve stuck closed bank 1).


I knew what this was right away because my buddy had the same code and had to replace his valves in his '07 a couple years ago. The funny thing is, mine drove just fine with the code. My buddies' was in "limp" mode, wouldn't go over 35 mph.

So I got online and bought the Secondary Air Injection Check Valve from Amazon for $199. The brand and model was the Dorman 911-643



I watched a few videos on the process. It's relatively straight forward. The Air Intake Valve sits on the back/top part of the engine, underneath and behind the Air Intake Manifold. The whole removal process took about 50 minutes. The installation process took about 90 minutes. It's really not too bad. The issue is, it can be very difficult to get to and remove the 2 bolts on the left and right side bottom of the valve body, holding it in place. You can see two of the bolt holes in the photo above on the far left side underneath the main body. There's one big hole for the air to flow through and two smaller holes where the bolts go.

So you have two options. You can either suck it up and attempt to remove the entire assembly, body and valves. Or, you can just remove the two valves on top which are the cause of the issue and held on by four T25 torx bolts per valve. The body is simply a cast piece that lets air flow through. I'm not saying the quicker, easier fix is the "best" option, but it is the one I chose.

One more note: while you have all of this stuff off, it might be a good time to change out your spark plugs if you haven't done them in a while. They are much easier to access when the intake manifold is off.

The job starts with the removal of the air intake manifold.



There are 8 bolts (4 on each side) and 2 nuts (one on each front side) that hold the manifold onto the engine. I believe the bolts and nuts are 12 mm if I remember right. There are also a lot of other bolts, hoses, clamps, clips, electric connectors, etc. to take off in order to remove the manifold. My suggestion is to take a bunch of pictures from multiple angles during each step before and during the process so you can refer to them when you re-assemble. One of the hardest parts of this process is removing two clips attached to the back of the manifold that hold a large wiring harness in place. They are circled in the next picture.



Each clip has a small tab behind and on the bottom. I was able to simply reach back there with my hand, find the tab with my finger, push the tab down, and pull straight back toward the firewall. Each of them came off pretty quickly. I've seen some guys have some major issues with these in some youtube videos. They really aren't that complicated. There is actually a similar clip on the top/left/rear of the intake manifold that you can use for practice. It has to come off as well. Once you get good at removing that clip, you should be just fine removing the two in the rear. Here is a picture of that clip. The small arrow points to the tab that needs to be lifted away from the clip. This clip is rotated around so you can see the tab. When it is installed, the clip is rotated back and the tab is on the backside/bottom.



Some guys don't remove the Throttle Body from the intake manifold. I chose to remove it so I could clean it up a bit. I used carb cleaner to remove all of the black residue. The throttle body is attached to the front where the large air box hose comes into the manifold. Here it is:



And here is the manifold (without the throttle body) removed from the engine:



And here is a picture of the engine with the manifold removed:



As you can see, there are 4 holes on each side where air is drawn in. On the right side, you'll see one of the manifold gaskets was stuck to the engine. The first thing I did was remove the gasket, gently clean up the area around all 8 holes, then cover the holes with rags so I didn't drop anything into the holes. That could be catastrophic. As well, I bought new gaskets on Amazon. Here is the name and part number for the gaskets: Fel-Pro MS 97044 Intake Manifold Gasket Set. The set was $15.

After covering the air intake holes, the next step is to identify and remove the secondary air intake valves. You can now see them sitting in the back/middle by the firewall. Here they are:



There are 4 torx bolts (T25) holding each valve to the valve body. I removed them with an extension and a ratchet. Be careful when removing the bolts. Do your best not to drop them down behind the engine; could be hard to find them. I reused the old bolts because the new ones were a tad longer than the old ones. I didn't want to chance the bolts bottoming out before they were tight. There's also an electric connector on each valve that needs removed as well as the two air hoses going into the front of each. Here are some pics of the old valves after I removed them. The one valve had visible moisture inside of it when I took it apart; probably what caused it to corrode and fail in the first place. I'm not sure how or why the moisture was in there. I placed the old parts on the new valve body so you could see how they went together.





Here is what the new valves look like once they're installed:



The next step is just to put the intake manifold back on and re-assemble everything. Don't forget to put your new gaskets on the manifold before you install it. I'm not guaranteeing that this way is better than replacing the whole part. Mine may fail 3 months from now, who knows. But, for a part that's only $199 and only takes 50 minutes to get to, I'll take my chances. If I can get 100,000 miles out of it, I'll be happy. Let me know if you have any questions.

 

Awesome work.

 

Nice write up.
I had this happen on my 07 except the valve was stuck open. The shop told me it'd be a ridiculous amount of $$ for the new secondary air valve installation and they've seen this as a common issue on the 2nd gen tundras. We opted for a bypass and all has been good since.

 

I had it happen to mine. Limp mode is actually not too bad. I was able to accelerate to 55 gently. Problems start if you decide to pass, you give it little bit more gas, but seem to be receiving less power. You give even more gas and get even less power. At some point you reach the floor and about 5k rpm, but truck keeps decelerating.

Dealer said it was 2k or 3k to replace, don't remember. They took care of it for free under a recall and I even got a free rental for those few days they had the pickup.

Funny thing is, truck started driving better after repairs than when it was new lol. Maybe I had the problem from the factory because truck had 12 miles when I got her back in 2010.

Before the pumps change, truck would often have this weird hesitation when trying to accelerate to pass for couple seconds and then power comes back like normal if you keep pushing more pedal. I always thought this was inherent issue with too much electronics or whatever. There were no codes to diagnosis(until final poop when it all broke finally). Learned to live with it.

 

Just started getting the P2441 on my 2007 Tundra (valve stuck closed bank 1). Haven't noticed any "limping" but about to take an 800-mi road trip and don't want to run into any issues. Looking into replacing the Secondary Air Injection Check Valve, but curious about your "bypass" comment. How do you bypass? Does bypass affect emissions and/or fuel economy? Also wondering if stuck valve will impact fuel economy.

 

There is a bypass kit that is made by Hewitt Industries. I have had the SAIS fail on me twice the first time @ 135k miles which was replaced under warranty, the second time at 255k miles this time I bypassed with a Hewitt 2nd gen kit I have had no problems since

If you do replace the valves use OEM the Dorman are a cheap alternative that will fail in a short amount of time. The internals of the valve is just a thin Reed valve ( it’s not a good design)

 

I 2nd the bypass kit! Easy install, and done forever!

 

Thanks for the feedback. Looking at getting the Gen 1 kit from Hewitt ($155 instead of $450 for Gen 2).

 

Don’t let the price make the decision for you. The Gen 2 is vastly superior. The Gen 1 will only help if the code is mechanical based, the Gen 2 will help with all codes except the pressure sensor in the valve itself. When I did mine I was tempted by the cheaper Gen 1

The main difference I see between the 2 kits is with the Gen 1 it is fooling the ECU to think it doesn’t need to run, with the Gen 2 you are replacing the stock module with a new one with different instructions for the ECU

 

I did a gen2 kit on a 2021 and removed all the SAIS. Then put headers without the air injector ports, has been working great for 20k miles.

 

Unfortunately, several unexpected financial requirements have limited my options. Based on your responses, would you recommend replacing $250 SAIS (oempartsquick.com) over $150 bypass? I've got 189,000 mi on it and maybe put 6k miles on it per year.

 

What headers? What did you do about cats?

 

ARH 1-7/8” headers (can be had with and without the air injection ports when you order). You can get high flow cats (200 cell) with that kit from ARH which I did (alternatively can reuse the front OEM 400 cells). Then I added large “mini cats” to prevent occasional “efficiency” error codes (can disable those codes with a tune too). The SAIS gen 2 and headers install can all be done in a driveway without having the truck on jacks or anything. The sound is pretty awesome and eliminating SAIS was great for my OCD.