Secondary air injection switching valve.......?

I would love some pics of that valve if you get a chance or the mechanic can take some pics and forward them to you.

Thanks

Kirk

 

with only 45k...

yup that falls under 5 yr 60k powertrain or the federal emmissions warranty.

That pump is directly related to BOTH of those warranties.

Also that pump runs more often then cold startups. Its a secondary air injection pump and is used to aid in the catalytic converters job, it pretty much runs all the time from my reading.

 

IM not buying that.

If the pump runs all the time, then there is no need for valves.

 

I'm planning on doing it in the morning so I'll post some pics when I do.

 

The 2TR (4 cyl) has had the pump since 2005. According to my Haynes manual, they only run during cold startup. Nd4spdbh is thinking of the secondary injection introduced in the 1960s and still used today in many vehicles. Most vehicles they do run all the time to help the cat do its job, but for some reason they only run on cold startup on these trucks, at least on the 4 cyl.

Good luck OP! I think cleaning them is a great idea. Always start cheap with repairs and go from there.

 

Then why is it that you can hear the pump spin down after a long drive (IE up to temp, not cold)?

 

I don't know, I have a Tundra. The pumps don't run after cold starts. I'm here to learn about the Tacoma system.

 

Yeah i have no idea either. I know it runs on cold starts, but also hear it almost every shutdown when its warm. I dont imagine it runs ALLLL the time (like the belt driven one on my old 79cj5 with the 4.2L I6) hence the need for the valves (maybe it closes at WOT or something) but im pretty sure its not JUST cold starts.

 

Yeah, I wasn't pleased to know that toyota is essentially putting the same system in 2015 models that they've been having issues with for nearly a decade now.

I'd love to make it to 200k without major issues like I did with my 1993 pickup.

 

I know from reading through all the info on the aip bypass that the reason for running during a cold startup is to get the cat up to temp quickly to make it work better at reducing emissions during those vital first 30 seconds .

Perhaps there is some logic to turn them on during shut down. I'm just spit balling because I don't actually know. It wouldn't be too hard to figure it out though.

Another thing I remember seeing while reason through all those threads was mention of a ECU update that Toyota released for the Tundras that kept the bypass from actually working. So if you do install a bypass on a recent model, test it out to make sure it actually works.

 

You're probably right, I was only going off of the 4 cyl and what my Haynes manual says specific to the 2TR. I was just making an assumption about the V6, it seems I shouldn't have done that. Sorry!

 

and thats the thing, i have NO idea either, theres really no literature on when the pump should come on and off.

 

I'm fully aware of the ECU Re flash on the tundra trucks. I have not done the Re flash, nor will I ever. It will kill my AIP mod. The re flash makes the pumps cycle at random times vs only on cold start up. When the pumps cycle, there is also a check on the pumps and valves. The mod makes these pumps and valves never come on and never get checked. This the ECU thinks the system is fine. With a re flash I will lose this feature.

If my truck goes to the dealer, there will be multiple notes placed on the vehicle stating no ECU Re flash. You can't trust the device writer to tell the tech to not fuck with the ECU.

Is there a recall get to Re flash the Tacomas ECU.

 

They run at shut down because on shutdown there is a small load of unburned fuel charge that gets dumped into the cats. The air pump blows fresh air in to help clear/burn out that unburned fuel to theoretically extend the life of the cats.

 

only reflash to note on the 12+ v6's is the TSB for the spark knock. No idea if they hid the new air pump stuff in that reflash or not.

And makes sense why it runs on shutdown to clear the system.

 

So, I finally got around to cleaning this switching valve. The CEL came back on this morning so I went ahead and cleaned it after work. For anyone who might search this in the future, I took a few pictures.

The air injection pump.



The 2 switching/diverter valves. Bank 1 is closest to the front of the truck or so I was told by the Toyota shop. They are located under the air hose.



Bank 1 valve. There's a whole lot of carbon build up for 45k miles, I think. I cleaned both the actual 'flapper' and the head of the valve. Got them cleaned up pretty good. I forgot to get pictures after.











The pump disassembled. The filter was pretty clean but I rinsed it and dried it anyway. All the vanes appeared to be intact. No excess dirt or trash.






I have no way to tell if this fixed until the second cold crank. I am not too hopeful that this fixed it but it's worth a try. They only sell the valves as a set that I could find. The cheapest was $475 or so. I'll post in a few days with what I come up with.

 

Thanks for posting. I've been wondering what they look like on the inside.

 

Yeah man.

 

That is the Secondary Air Pump from a 2010 GX 460 and that's typically what I find whenever there is a problem with the Secondary Air Injection System.

Good luck with your repairs, hopefully that check engine light will not return!

 

So, , today was the 3rd cold crank and no CEL yet. Possibly jumping the gun and jinxing myself by posting this soon, but it's a possibility that I may have cleaned enough carbon out to last me a while longer.