Is the Rutech SAIS bypass kit the easiest to install and are the block off plates necessary?

[Francis K]

Picked up a 2007 LC for my mom just getting her all 100% buttoned up, I have an extensive baselining list compiled but I'm getting caught on the potential SAIS issue. No codes at the moment and obviously I would like to keep it that way.

I'm barely a half a banana dumb donkey mechanic and it looks like the rutech kit is the easiest to install, it's seemingly plug it in and all set. A bit hung up on the block off plates, if I don't have codes do I actually need them? If I do need them can anyone point me to where they go exactly?

Thank you sincerely!

 

[Rhetoric]

Do not install these hack kits. Refresh the SAIS system and move on with life. I have nearly 300k miles on mine.

 

[Francis K]

Do not install these hack kits. Refresh the SAIS system and move on with life. I have nearly 300k miles on mine.

How? Remove the intake manifold and change the filter?

From what I understand the SAIS is just some emissions garbage on a 20 year old vehicle, what do you see as the issue in bypassing it?

Thank you for your input

 

[AARONTLC]

Francis, I don’t have a later model LC but I follow this forum religiously. The inexpensive SAIS bypass kits have been tried many times and seem to disappoint at a high level. @2001LC has put a LOT of time and money into creating a bulletproof upgrade to the SAIS system. I am looking for a late model GX470 for my wife and the first thing I am going to do is his upgrade. Do a little searching under his name and the thread will give you a step by step on how to troubleshoot and install his upgrade. Good luck!

 

[Francis K]

Francis, I don’t have a later model LC but I follow this forum religiously. The inexpensive SAIS bypass kits have been tried many times and seem to disappoint at a high level. @2001LC has put a LOT of time and money into creating a bulletproof upgrade to the SAIS system. I am looking for a late model GX470 for my wife and the first thing I am going to do is his upgrade. Do a little searching under his name and the thread will give you a step by step on how to troubleshoot and install his upgrade. Good luck!

Thank you brother I did see that thread, funny I used that same filter myself on my GX460 but it was right there in the open to do.

So kinda sounds like if I really want this thing reliable for my mom then I'm going to have to remove the intake manifold and deal with the SAIS filter...

 

[NE Snowman]

I bought a pre VVTI and this was one of the reasons, I just didn’t want to deal with emissions SAIP.

I will admit under the recommendation of a friend (T4R supported) both my VVTI 4Rs I installed them without block off plates. I never had codes when I purchased the trucks and they never came on. 191k -> 234k sold because of rust, 158k -> 213k still going and it’s just not giving me problems so I haven’t gone to look for problems.

If I bought a VVTI LC, I’d go with 2001s solution.

 

[2001LC]

I've came-up with inspection, for the S.A.I. filter.

Where I use, a 6mm directional camera lens borescope, to inspect the S.A.I. filter. So, I can give recommendations, as to timing of doing the S.A.I. filter MOD. Since we must remove intake manifold in the 4.7L 2UZ-fe VVTi, to get to the S.A.I. filter. We'll typically do the starter job, at same time. Starters, tend to fail about 250K miles on average. So it cost effective to push off remove intake manifold until then.

Filter visible:

Filter gone from view:

I now know. The S.A.I. foam rubber filter, is shrinking. Then being suck down into impeller.

I found an 07LC w/24K mile early this year (2025). That came from 80 miles north of Batten Rouge LA. Where all foam on this 07LC had texture of sand. Touch any of its foam rubber and it disintegrate. Its filter was out of position (not visible). I found filter in the S.A.I. pump cap, nearing the impeller. Was crumbled like sand, when touched.

A Toyota/Lexus GX460 recall TBS. Suggested, moisture played a roll in filter failure. I have found The Climate has a great deal, to do with condition of filter. In dry moderate climates, like found in Denver, they last a very long time. But in very cold or hot or hot humid climates, they'll fail faster. Humid climates, failures happen the fastest.

I've seen 3 different (two pictures below) filters designs. IMHO all will fail. Why Toyota has adapted replaceable, IDK!.
1st gen

2nd gen

 

[Francis K]

I've came-up with inspection, for the S.A.I. filter.

Where I use, a 6mm directional camera lens borescope, to inspect the S.A.I. filter. So, I can give recommendations, as to timing of doing the S.A.I. filter MOD. Since we must remove intake manifold in the 4.7L 2UZ-fe VVTi, to get to the S.A.I. filter. We'll typically do the starter job, at same time. Starters, tend to fail about 250K miles on average. So it cost effective to push off remove intake manifold until then.

Filter visible:
View attachment 4022095
Filter gone from view:
View attachment 4022093

I now know. The S.A.I. foam rubber filter, is shrinking. Then being suck down into impeller.

I found an 07LC w/24K mile early this year (2025). That came from 80 miles north of Batten Rouge LA. Where all foam on this 07LC had texture of sand. Touch any of its foam rubber and it disintegrate. Its filter was out of position (not visible). I found filter in the S.A.I. pump cap, nearing the impeller. Was crumbled like sand, when touched.
View attachment 4022100

A Toyota/Lexus GX460 recall TBS. Suggested, moisture played a roll in filter failure. I have found The Climate has a great deal, to do with condition of filter. In dry moderate climates, like found in Denver, they last a very long time. But in very cold or hot or hot humid climates, they'll fail faster. Humid climates, failures happen the fastest.

I've seen 3 different (two pictures below) filters designs. IMHO all will fail. Why Toyota has adapted replaceable, IDK!.
1st gen
View attachment 4022108
2nd gen
View attachment 4022101

This is invaluable brother thank you, it's been a Michigan truck for the past few years and Georgia before that. I guess I have a decision to make, either wait for the starter to fail and do it then or just call it preventative maintenance and do it now with a new starter. Would a third option be to perhaps use the bypass kit until the starter needs replacing? Would the bypass kit buy that time?

 

[medtro]

Francis, I don’t have a later model LC but I follow this forum religiously. The inexpensive SAIS bypass kits have been tried many times and seem to disappoint at a high level. @2001LC has put a LOT of time and money into creating a bulletproof upgrade to the SAIS system. I am looking for a late model GX470 for my wife and the first thing I am going to do is his upgrade. Do a little searching under his name and the thread will give you a step by step on how to troubleshoot and install his upgrade. Good luck!

May be do this for less money?

https://www.toyota-4runner.org/5th-gen-t4rs/259953-secondary-air-pump-mod-validity.html

 

[aging fleet]

I wouldn't preemptively do the bypass, just roll with it until you have an issue.

 

[Francis K]

May be do this for less money?

https://www.toyota-4runner.org/5th-gen-t4rs/259953-secondary-air-pump-mod-validity.html

Funny I have this done on my GX460 the issue with the LC from what I have researched is that to do this the intake manifold has to come off....do I not have that right? Is this not the same as what @2001LC figured out except with the extended hose to be able to easily change the filter?

 

[aging fleet]

I've replaced the entire SAI system on my '06 over the years, to put hands on any of the components, the intake manifold must come off.

 

[Francis K]

I wouldn't preemptively do the bypass, just roll with it until you have an issue.

So just roll with it and if s*** happens then do the bypass or when it comes time to do the starter then handle it? I was under the impression that once you get to the problem stage it becomes a whole other can of worms...

 

[aging fleet]

So just roll with it and if s*** happens then do the bypass or when it comes time to do the starter then handle it? I was under the impression that once you get to the problem stage it becomes a whole other can of worms...

Guess it's a personal choice, my SAI pump got noisier than I was comfortable with back in 2021 at around 145k miles so I replaced it. In 2023 at 155k miles it threw a code for an SAI switching valve. At that point I replaced all three switching valves, the starter, and all the vacuum lines underneath the intake manifold. I chose not to bypass because all the parts to fix it are available, I can sell it to someone in a SMOG testing city/state without worries, and I'm not dealing with a non-factory solution.

The 'once you have a problem, it's too late' point of view is more applicable if you plan to bypass the system.

 

[Francis K]

Guess it's a personal choice, my SAI pump got noisier than I was comfortable with back in 2021 at around 145k miles so I replaced it. In 2023 at 155k miles it threw a code for an SAI switching valve. At that point I replaced all three switching valves, the starter, and all the vacuum lines underneath the intake manifold. I chose not to bypass because all the parts to fix it are available, I can sell it to someone in a SMOG testing city/state without worries, and I'm not dealing with a non-factory solution.

The 'once you have a problem, it's too late' point of view is more applicable if you plan to bypass the system.

Okay so what you're saying is that it's not necessarily automatic catastrophe when that filter gets sucked in...really good to know

 

[2001LC]

Just "rolling the disc" is a very bad idea! Borescope, loads the dice in your favor.

If filter out of view. It is either ground up or will be. Filter, debris in filter, dust from engine valley along with dust atmosphere will travel through the S.A.I. system. Then in to exhaust ports of heads, onto exhaust valve steam & seat. The on into combustion camber. Then on to A/F sensor, CAT and O2.

This can result in expensive damage:
S.A.I. system $1,200.
Engine $15,000 (current estimate from my local dealership, installed)
CATs $4,000
A/F $300
o2 $200

 

[Francis K]

Just "rolling the disc" is a very bad idea! Borescope, loads the dice in your favor.

If filter out of view. It is either ground up or will be. Filter, debris in filter, dust from engine valley along with dust atmosphere will travel through the S.A.I. system. Then in to exhaust ports of heads, onto exhaust valve steam & seat. The on into combustion camber. Then on to A/F sensor, CAT and O2.

This can result in expensive damage:
S.A.I. system $1,200.
Engine $15,000 (current estimate from my local dealership, installed)
CATs $4,000
A/F $300
o2 $200

Sincerely appreciate you chiming in brother, can you provide me some more info or point me in the direction of where to stick the scope specifically to catch a view of the filter?

 

[2001LC]

I snake my borescope camera, in from drive side of throttle body, under intake manifold over the top of the S.A.I. pump cap. Follow the air intake port on cap to it's end and look back into air intake port. It's a tight fit, that my 6MM camera/snake fits easily.

Path I take, with my 6mm borescope snake is the green line. Intake manifold would be on, during inspection of S.A.I. filter..

FWIW: The engine above. Was severely overheating. That's why block is red and debris not cleaning from top of engine, before intake manifold removed.

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

Dec 11, 2021

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 2006 & 2007 100 series Toyota Land Cruiser & Lexus LX470 manufacture in Japan for the USA market.
It also applies to all 4.7L 2UZ-fe VVTi such as in the: GX470, 4Runner, Sequoia, etc. Every 2UZ-fe 4.7L VVT engines, S.A.I. filter will fail. AND then get CAT...

• 2001LC
• Replies: 134
• Forum: 100-Series Cruisers

• 

 

[medtro]

Funny I have this done on my GX460 the issue with the LC from what I have researched is that to do this the intake manifold has to come off....do I not have that right? Is this not the same as what @2001LC figured out except with the extended hose to be able to easily change the filter?

Yes, manifold has to come off. @AARONTLC mentioned that @2001LC spent a lot of time and money into the upgrade. I am not familiar with that upgrade so I don't know if they are the same. I was simply suggesting an alternative that cost $20 to change out the factory foam filter with a uni filter. Many documented positive results since 2018.

Here is another solution that is free 90% of the time. Copy from https://www.toyota-4runner.org/1757291-post13.html.

Listen, most of the times this is an easy fix, and can be done in a few hours with hand tools for NO money 90% of the time.

The inlet pipe for the air pump has a foam filter, which over time with engine heat cycles,starts to deteriorate. When it does it gets sucked into the pump (occasionally damaging some fins in the pump, generally not enough damage to cause the pump to not work), and push the little bits of chopped foam straight into the valves. This causes them to stick.

Snatch off the intake, remove the foam filter, and blow out the pump with compressed air. Remove the valves and use a power probe (or a jumper wire from a 12v source, IE your battery) to actuate the valves and remove any pieces of foam stuck. Then reassemble and you're done. Iv done this to countless tundra's and 4runners and have had VERY few need actual parts replacement, although occasionally it is necessary.