S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert! (1 Viewer)

[bdobyns]

So, if I am reading this correctly, the 06 and 07 4.7’s have the SAIS, located under the intake manifold on the back near the firewall. Either at the same time or at different times, will start throwing p1442, 45 and possibly 2441 codes (which could throw the rig into limp mode, right?). The filters used in the fan with the plastic fins disintegrates over time, allowing for non filtered air to pass through the SAIS and then into the exhaust manifold and eventually the cats. This unfiltered air contains contaminants that will eventually cause the cats to fail 420/430 codes. Just curious, the SAIS fan forces outside air into the exhaust manifold, where is it pulling the outside air from?

Because the SAIS codes will affect the drivability of the rig, it would seem that the first point to address is the SAIS codes and your solution is to, and I might be reading into this, is remove the old filter from the fan housing and install a replaceable filter. Can’t wait for the details on that.

Of course we, myself included, know that you can use the Hewitt solution which is to bypass the SAIS and install block off plates between the SAIS where it joins the exhaust manifold, legal or illegal, what this does is prevent any contaminant from getting into the exhaust and to the CATs. And yes, we know that it is not legal.

However, will either one of these options actually clear the 420/430 codes? I would assume that if you are getting these codes, your CATs have already been damaged, possibly from the SAIS, but the fix that you are talking about seems more of a preventive measure that one should take in order to not get the dang CAT codes. Once the CATs are bad, seems that the only solution to get your rig to pass smog is replace the CATs or maybe the O2 sensors which might be reading poorly.

 

[2001LC]

So, if I am reading this correctly, the 06 and 07 4.7’s have the SAIS, located under the intake manifold on the back near the firewall. Either at the same time or at different times, will start throwing p1442, 45 and possibly 2441 codes (which could throw the rig into limp mode, right?). The filters used in the fan with the plastic fins disintegrates over time, allowing for non filtered air to pass through the SAIS and then into the exhaust manifold and eventually the cats. This unfiltered air contains contaminants that will eventually cause the cats to fail 420/430 codes. Just curious, the SAIS fan forces outside air into the exhaust manifold, where is it pulling the outside air from?

Because the SAIS codes will affect the drivability of the rig, it would seem that the first point to address is the SAIS codes and your solution is to, and I might be reading into this, is remove the old filter from the fan housing and install a replaceable filter. Can’t wait for the details on that.

Of course we, myself included, know that you can use the Hewitt solution which is to bypass the SAIS and install block off plates between the SAIS where it joins the exhaust manifold, legal or illegal, what this does is prevent any contaminant from getting into the exhaust and to the CATs. And yes, we know that it is not legal.

However, will either one of these options actually clear the 420/430 codes? I would assume that if you are getting these codes, your CATs have already been damaged, possibly from the SAIS, but the fix that you are talking about seems more of a preventive measure that one should take in order to not get the dang CAT codes. Once the CATs are bad, seems that the only solution to get your rig to pass smog is replace the CATs or maybe the O2 sensors which might be reading poorly.

First can I ask, that you give detail on: why you installed the block off kit. What else was done? What codes (DTC) you may have or had before and after???

Location of AI pump main switch and it's air intake port:
SAIS or AI pump and main SW, are under intake manifold near front of engine just back of radiator fan forward of starter. AI SW's BK1 & BK2 SW are on water bypass joint rear (near fire wall).


No limp mode:
These stuck closed codes (DTC) of A.I. do not put vehicle in limp mode. Nor do P0420 or P04230. We just get a CEL if DTC are confirmed. The VSC shut down as a result. Any engine, ABS, transfer case or Transmission DTC will shut down VSC. So no big deal with driving, unless you need VSC. But you'll not likely pass emission test if the inspector see CEL, for sure not if he check codes. They are all emission related DTC.

Yes: "The filters used in the fan with the plastic fins disintegrates (one possibility) over time, allowing for non filtered air to pass through the SAIS and then into the exhaust manifold and eventually the cats. This unfiltered air contains contaminants that will eventually (MAY) cause the cats to fail 420/430 codes. Just curious, the SAIS fan forces outside air into the exhaust manifold, where is it pulling the outside air from?"

A.I. Air is pulled from:
A.I. Pump, pulls air from under the intake manifold, just behind radiator cooling fan area, from engine valley. Pump has a 1"OD by ~4" tube come out of side of it's top, which it draws air through.

End of A.I pump air draw tube, circled in yellow.

Anyone that has done a starter jobs, knows how much dust build in the valley. Add in nest from rodent, etc, it's a nasty mess under there.

I showed the aftermarket filter in first post #2. Here's rout revealed, simple right!
Took me time to come up with the routing and materials. My first thought was to rout to firewall. But this is much shorter piping, cleaner and gives easy access to replace filter. I'll be posting detail on how and where to get materials I used.

Location of A.I Bk1 & BK2 switches, along with air pipes from each of them to exhaust header.

Yes, Hewitt block off kit work to close A.I. air passage to CAT. Which then make vehicle it's on, only legal to drive off-road as you know! So once blocks in place, no air/containment can reach heads or CATs through the AI system. They place blocking plate between air pipes and exhaust headers. I understand the $500 block off kit, you must also remove intake manifold. But that is hear-say, as I do not do install them. Why not? Because, all 100 series that come to me are driven on city streets and HWY, at minimum to get off road. I understand why so many have blocked off. For one, they knew of no other solution.

A.I filter failure is one reason A.I. system go bad. Primary reason IMHO. Failure of or fear of failure of A.I. system, is why people use the block off kits. I've seen post in mud, A.I.. pump get louder and sound like turbo or vacuum cleaner just before failure. My pump sound likely that daily for a about a year, never changed. Which I found was due to filter being near total gone. So very likely many with the Hewitt block, if they look in A.I. pump, will find filter gone partially or completely.

Yes, Filter mod as PM. absolutely IMHO:
This will prevent A.I. system and CAT from damage, that is do to A.I. filter failure. Which could save thousand in repair cost.

Yes, Filter mod should be installed after we get A.I. system and/or CATs damage, if not already in:

If A.I. and or CAT already damaged caused/due to A.I. blowing unfiltered air through the system. You must correct problem that "cause" damage first thing, or problems comes back. Many have just slapped in new CAT, just to have go bad again.

Cause must be found and corrected, before fixing any issue. A flat tire from a nail, remove the nail before patching. This is especially true of CATs. In this case of A.I. filtration failure; replace the A.I. pump which comes with new filter sealed in it. Or my solution, remove factory non replaceable filter and install a replaceable aftermarket filter. Then replace other parts as necessary, like CATs.

 

[bdobyns]

The block off kit was to get me out of limp mode using the gen 1 bypass, including blockoff plates. Kept getting cel with 1442 and 1630 codes. Switched to gen 2 bypass and only getting 430 constantly and sometimes 420. Because i have blockoffs installed, i will not be needing to fix sais with filter as you have shown, howere, next time intake must be removed i will address it as the cats have gone and those need to be replaced however, with block offs, i shouldn't be getting any crud hitting the cats. The most difficult pill is the cost of parts for both cats and sais. cats alone are running over $4500 in CA! That is like 25% of the value of the truck! Add SAIS, what is that, 35% of the value of the vehicle...cant even sell it without passing smog.

 

[Mars06LC]

First can I ask, that you give detail on: why you installed the block off kit. What else was done? What codes (DTC) you may have or had before and after???

FWIW on mine I had cat codes (P0420/30) about 1-2 years before I got SAIS codes (can’t recall what codes but recall loud fan noise coming from the unit). I installed the SAIS bypass kit which took care of the SAIS codes, and installed o2 spacers which took care of 0420/30 codes.

 

[jtb517]

Drum roll.............the fix... replaceable filter! HA!

Once install, is a $20, 3 second no tool PM. So easy...

Patiently waiting to see the no tool solution.

 

[2001LC]

The block off kit was to get me out of limp mode using the gen 1 bypass, including blockoff plates. Kept getting cel with 1442 and 1630 codes. Switched to gen 2 bypass and only getting 430 constantly and sometimes 420. Because i have blockoffs installed, i will not be needing to fix sais with filter as you have shown, howere, next time intake must be removed i will address it as the cats have gone and those need to be replaced however, with block offs, i shouldn't be getting any crud hitting the cats. The most difficult pill is the cost of parts for both cats and sais. cats alone are running over $4500 in CA! That is like 25% of the value of the truck! Add SAIS, what is that, 35% of the value of the vehicle...cant even sell it without passing smog.

FWIW on mine I had cat codes (P0420/30) about 1-2 years before I got SAIS codes (can’t recall what codes but recall loud fan noise coming from the unit). I installed the SAIS bypass kit which took care of the SAIS codes, and installed o2 spacers which took care of 0420/30 codes.

When the day comes, either of you, pull the intake manifold. I'd be supper interested in condition of your AI pump filter?

 

[2001LC]

Patiently waiting to see the no tool solution.

No tool Solution, is the filter you see. Pull off by hand and replace it!

The mechanics to make accessible, is in the picture.

Picture is worth a thousand words.

 

[jtb517]

I did see that photo. My interest is more in the hose and routing. Can that be installed without the intake manifold removed?

 

[2001LC]

I did see that photo. My interest is more in the hose and routing. Can that be installed without the intake manifold removed?

NO! Intake manifold must be removed.
The top of the A.I. pump should also be remove, too remove its factory filter. Note: "Top" is sealed to the A.I. pump, with a glue. So heating the top plastic to soften the glue, is advisable.

Looking (11 to 4 o'clock position) closely at where top was sealed to A.I. pump. You can see some of the plastic of the top, broke away and is still glued to the pump. Of the twp pumps I removed tops from, without heating first. 1 of 2 broke..

 

[2001LC]

I've now added detail to post #4 of this thread. Detail of parts, assembly and install of this external A.I. Pump filter.

S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert!

We've a $2.00 part in the S.A.I. (secondary air injection) system of the VVT engine, that is taking-out ~$7,000.00 $15,000 $25,000 (inflation) in parts. WOW! I've a very easy and cheap WORK AROUND. You are going to love this ;) This thread is dedicated to the 4.7L 2UZ-fe VVT engine, in the...

forum.ih8mud.com

For those that need more detail, please ask here in this thread (not in a PM). If you need detail of "how to step by step R&R intake manifold". Just look for starter jobs step by step in mud.

If you feel this not a DIY for you, I'll do for you.

Personally I can not recommend most any shop in the world. I hate seeing starter jobs done by anyone but me. WHY; Most shops just will not take the time needed to clean before, during and after. Even the best mechanics around, typically only use shop air to blow off grim first, from the head to intake manifold area.

Rule: DO NO HARM! Which it takes time to clean very very well. Pro shops can't afford the time.. heck, I spend more time cleaning, than most do doing the job.

 

[jtb517]

NO! Intake manifold must be removed.
The top of the A.I. pump should also be remove, too remove its factory filter. Note: "Top" is sealed to the A.I. pump, with a glue. So heating the top plastic to soften the glue, is advisable.

Looking (11 to 4 o'clock position) closely at where top was sealed to A.I. pump. You can see some of the plastic of the top, broke away and is still glued to the pump. Of the twp pumps I removed tops from, without heating first. 1 of 2 broke..

I interpreted no tool solution as there was some way to install without removing the manifold. I was under the hood last night and was thinking there is no way I can snake a hose in there.

 

[2001LC]

I interpreted no tool solution as there was some way to install without removing the manifold. I was under the hood last night and was thinking there is no way I can snake a hose in there.

Sorry if I didn't make clear. It's a no tool PM, once installed. It that, one can then replace filter on regular basis, without pulling intake manifold each time.

 

[2001LC]

@BCM I was thinking about you.

P1442 or P1445 coming up with all A.I. components checking out as OKAY. Was solved in my case.

Anyone getting these, "could" mean contaminates have entered the primary switch and or it's pressure sensor. This "could" be sign filter is damaged or gone. In post #3, I talk about this some. Where I replaced the main SW and no more codes for BK1 (P1442) or BK2 (P1445 )SWs.

If this is the case and my oppinon, the lose of A.I. pump filter is taking out the CAT. Well! you get my drift!

 

[kpz1234]

Not sure if cross posting is okay, but I was searching this mod on another board and one person reported in the comments that particles from the red filter ended up wrecking his pump.

Secondary Air Injection Pump Mod on 5th Gen 4Runner

Secondary Air Pump Mod on 5th Gen 4Runner, Air Injection Pump Preventative Maintenance Filter Modification, Uni Filter Mod

trail4runner.com

 

[BCM]

@BCM I was thinking about you.

P1442 or P1445 coming up with all A.I. components checking out as OKAY. Was solved in my case.

Anyone getting these, "could" mean contaminates have entered the primary switch and or it's pressure sensor. This "could" be sign filter is damaged or gone. In post #3, I talk about this some. Where I replaced the main SW and no more codes for BK1 (P1442) or BK2 (P1445 )SWs.

If this is the case and my oppinon, the lose of A.I. pump filter is taking out the CAT. Well! you get my drift!

Thanks Paul. Coincidently. I installed the 'alternative' fix yesterday.

 

[2001LC]

Thanks Paul. Coincidently. I installed the 'alternative' fix yesterday.

Was the "alternative" requiring intake manifold be pulled?

 

[BCM]

Was the "alternative" requiring intake manifold be pulled?

Nope, just loosening a few 10mm nuts and inserting a couple of plates. I know this isn’t your preferred method, but it quick and appears to have addressed the issue. Plus, should prevent any debris making it to the cats.

 

[2001LC]

Not sure if cross posting is okay, but I was searching this mod on another board and one person reported in the comments that particles from the red filter ended up wrecking his pump.

Secondary Air Injection Pump Mod on 5th Gen 4Runner

Secondary Air Pump Mod on 5th Gen 4Runner, Air Injection Pump Preventative Maintenance Filter Modification, Uni Filter Mod

trail4runner.com

Thanks for the link.

I had seen it some time ago, but I did not read the post about aftermarket (UNI) filter failure:

__________________________________________________________________________________
Matt:
"so I just wanted to put in my experience with this mod and you can take from it what you want to. I did this on my 2020 5th gen 4runner and at first no problems at all for about 5 months, then out of no where it went into limp mode while out and about. I got it to the dealership and ran the usual diagnostic test and came up with a pump failure code, they tried to reset it still didn’t work so they looked deeper into the situation noticed that I had done this mod and found a lot of red particles that had clogged not only the main pump but also a valve and another pump on the left head. so do this at your own risk! the filter was as clean as a whistle when installed, so just be carful this mod cost me 1,500!!!

I’m not saying this doesn’t work I’m just saying that it could happen. the mod that was supposed to prolong it from the bits of the stock filter screwing it up actually screwed it up

STEPHEN SULLIVAN:
Matt was asked by Stephen: What do you think caused the red particles ? Did you wash the uni filter before installing ?

Matt:
I cleaned the filter out before installing could have just been my luck with that one filter who knows, I just wanted to post what happened to me because it could happen to anyone and it sucks when it does. I figure the only reason why this mod is posted is due to the stock foam filter inside deteriorating over time so I would say every 3 to 4 years or when ever you feel like it change it out, problem solved lol. My opinion I would leave it be.
"
___________________________________

It's unclear if he cleaned the new filter, before installing it. But:

I spoke with the manufacture about these filters. One thing we talked about, was cleaning the filter. It is not recommended to clean these filters. Although it looks like a K&N lifetime cleanable cotton filter it is not cleanable.

So perhaps it was his cleaning that cause filter failure. These are compressed foam filters. It's recommended they be changed 3yr or 20K miles IIRC.

If K&N makes a 1", I may try it. But the UNI foam filter has been used for years on small carburetors like motorcycle.

 

[2001LC]

Is the filter of the S.A.I. pump (blower) disintegrating, This is the big question here?

I hope others will inspect for and report back here in this thread, their S.A.I. filter condition?
I've also ask about this in other threads, one being the Hewitt block thread.


Question I have:
Why was my S.A.I. pump filter all but a fragment gone?

Did a mouse eat it? Valley had signs of rodents and repairs were done many years earlier for rodent damage!

Was it a defective A.I pump filter, a one off?

Will all these filters fail at some point?
______

Well if rodent, which would likely have to be a baby to get into pump air inlet. Which unlike the 4runner or other models, does not have a plastic inlet cap. So sure, it could be rodents damage. I see 1 in 4 100 series with rodent damages. They love to nest under the intake manifold. But first time we bring up to operating time, they're done!

But one interesting thing that I've mention before, which took me down this road. Was an ebay listing for rebuilt A.I pumps. Guy claimed to master Toyota mechanic and rebuilds these. Said it's the filter failing, which he replaces. This implies our filter are failing on their own.

As I also noted earlier. I've been looking for the pasted year, for others with same DTCs (CATs & A.I.) and I found one locally. He said his A.I. filter also was gone. No mention of rodents.
_______

Two things are for sure:
1) All filter will become clogged and need replacing with time.
2) Very unlikely a rodent will eat through the rubber hose mod I made. Besides: they tended to eat wire sheathing (soy) more than anything.

Toyota corp:
Toyota is unlikely to say anything, if they've found issue here with filter. Why, a recall would be forced on them, and they'd own everyone that has had repairs done, because of. When dealing with environmental issue, the USA takes a strong stance. Especial these days with the freaky weather, we're all seeing.

The TSB they have out, states if debris found in system. How can debris get into system, that is filtered! It can't. Again points to filter failure!

 

[jerryb]

they get wet, and then they disintegrate. It's open cell foam.
they don't suck in water or probably won't like the tundra twin pumps, but the moisture and condensation is there.
they will deteriorate from just being wet over time.
can you believe where toyota put those pumps on the tundras? There's a 5.7 tundra teardown on the popular utube guy that does ALL the teardowns. Lot's of visuals on the twin pump with long tubes to the switching valves. Much like the 4runners as far as plastic pipes to the rear valves.