I know a lot of '06-'07 owners bypass the SAI system when it starts to go bad, I'm going to try to fix it. (1 Viewer)

[aging fleet]

Or I might end up making worse, we'll find out.

'98-'05 owners, this is the part where you laugh and say, I told you not to buy an '06 or '07 aging fleet. Well, I didn't listen. I wanted the extra horsepower so now it's time for me to pay the vvti tax. I chose not to bypass the system because I'd prefer to have everything work how it's supposed to. That's just a personal preference given replacement parts are readily available, but I totally understand why people choose to bypass the system.

Some background, my '06 has around 153,000 miles and I replaced the air pump back in '21 because it was it was getting noisy and I was afraid it would fail. At that point, I didn't replace the starter or any of the other SAI components. Last winter when the temps dropped below 20 degrees F, I started to throw a DTC because one of the air switching valve was sticking open, or maybe closed, I don't remember. It would resolve itself on longer trips and would stay away until the next cold start.

I ordered parts over the summer and, because it's getting cold again, it's time to cross this project off the list. For anyone that wants to go down this path after me, here are some part numbers. Air pump isn't included (already replaced), but I am doing the starter while I'm in there.

At this point, I've got everything taken apart, but haven't started putting things back together again. The weather should be nice all week so the 40 can do daily duties. I need to order a few parts I wasn't expecting to replace, so far a few brittle cracked hoses and my heater Ts are probably ready after 8 years. I'm hoping to have it all back together in about 5 days.

Some tips so far, you need a top-side creeper or something that will allow you to get on top of the engine to get the intake off and reach all the crap you need to unbolt at the back of the engine. Thanks @Zuberg, for that heads up.

Despite what the FSM said, I didn't drain my coolant and didn't pull the coolant crossover pipe at the back of the engine. It's possible to pull the starter with all that in place, but I did remove the No. 2 air switching valves before attacking the starter. I also removed the bolt holding the electrical connectors on top of the transmission, this made it possible to remove the driver's side starter bolt. Thanks @2001LC for that tip. Once the starter was loose, I was able to turn it counter clockwise and remove the electrical connections.

My creeper.

The current state of affairs

I'm actually not even sure which valve was causing the DTC, but I do know I don't want to pull the intake again so I'm replacing all of it.

That's it for tonight, hopefully I'll get parts ordered tomorrow and maybe start putting things back together after the kids go to bed. Let me know if there is anything else I should to while "I'm in there".

 

[Rhetoric]

Beautiful. Just beautiful. I will be doing the same to my 256k mile truck in the next year. I will also be doing the @2001LC filter mod.

 

[aging fleet]

Beautiful. Just beautiful. I will be doing the same to my 256k mile truck in the next year. I will also be doing the @2001LC filter mod.

I may do that too if I can find a filter locally.

 

[aging fleet]

I only had about an hour to mess with it tonight, but the new starter is on as well as the passenger side No. 2 switching valve. That cream colored cover over the harnesses to the right of the starter will be incredibly brittle like everything else made of plastic in that area. You have to pop off a portion of it to access the bolt that secures the wire sending power to the starter. It's going to break to some degree when you mess with it.

I had two sections of vacuum hose on hand so I replaced the lines going to the valves. 90999-92003 is 600mm or about 2', if you want a longer length 90999-92006 will get you 4'.

New vacuum hoses that run to the power steering pump and heater Ts have been ordered and should be enroute soon from Dubai.

 

[excessive]

optional "while you're in there" items for the intake manifold out:

1. injector seals / baskets
2. Throttle body coolant hoses
3. replace wire connectors on knock sensors (mine were brittle at only 150k miles)
4. valve cover gaskets ( careful not to break bolts on these, ask me how i know)
5. PCV valve + hose
6. check all evap hoses for wear & leaks

 

[vipergrhd]

I'm not sure if those little boogers (Knock sensor) ever go out on a 2UZ but when my knock sensor went out on my 93 3VZE it was running poorly like it went into full retard. I end up getting a sensor and wire overlay.

 

[SteveH]

I recently had a knock sensor fail on my '99 and the engine ran the same as it always did. Oddly, all the under-manifold connectors were not brittle (at 314K) and behaved nicely. I replaced both knock sensors with OEM Toyota, and the code went away and all is well. Knock sensors were $156/ea.

 

[aging fleet]

@SteveH, awesome your connectors held up. Two of mine lost their locking tabs during this process or back in '21 when I replaced the pump, I wasn't going to re-pin a new connector so I just used a zip tie to secure them.

I stared at the knock sensor for a bit after reading @vipergrhd 's post and decided to just run the originals and hope for the best. My power steering vacuum hoses and heater Ts won't be here until Monday (think they got held up due to a few 40 parts I added to the order) so there are still a few more things I need to do before this is totally wrapped up.

@excessive, I've read your thread, I re-torqued the valve covers then slowly and carefully backed away from them.

 

[2001LC]

Or I might end up making worse, we'll find out.

'98-'05 owners, this is the part where you laugh and say, I told you not to buy an '06 or '07 aging fleet. Well, I didn't listen. I wanted the extra horsepower so now it's time for me to pay the vvti tax. I chose not to bypass the system because I'd prefer to have everything work how it's supposed to. That's just a personal preference given replacement parts are readily available, but I totally understand why people choose to bypass the system.

Some background, my '06 has around 153,000 miles and I replaced the air pump back in '21 because it was it was getting noisy and I was afraid it would fail. At that point, I didn't replace the starter or any of the other SAI components. Last winter when the temps dropped below 20 degrees F, I started to throw a DTC because one of the air switching valve was sticking open, or maybe closed, I don't remember. It would resolve itself on longer trips and would stay away until the next cold start.

I ordered parts over the summer and, because it's getting cold again, it's time to cross this project off the list. For anyone that wants to go down this path after me, here are some part numbers. Air pump isn't included (already replaced), but I am doing the starter while I'm in there.

View attachment 3479934

At this point, I've got everything taken apart, but haven't started putting things back together again. The weather should be nice all week so the 40 can do daily duties. I need to order a few parts I wasn't expecting to replace, so far a few brittle cracked hoses and my heater Ts are probably ready after 8 years. I'm hoping to have it all back together in about 5 days.

Some tips so far, you need a top-side creeper or something that will allow you to get on top of the engine to get the intake off and reach all the crap you need to unbolt at the back of the engine. Thanks @Zuberg, for that heads up.

Despite what the FSM said, I didn't drain my coolant and didn't pull the coolant crossover pipe at the back of the engine. It's possible to pull the starter with all that in place, but I did remove the No. 2 air switching valves before attacking the starter. I also removed the bolt holding the electrical connectors on top of the transmission, this made it possible to remove the driver's side starter bolt. Thanks @2001LC for that tip. Once the starter was loose, I was able to turn it counter clockwise and remove the electrical connections.

My creeper.
View attachment 3479976

The current state of affairs
View attachment 3479981

I'm actually not even sure which valve was causing the DTC, but I do know I don't want to pull the intake again so I'm replacing all of it.
View attachment 3479988

That's it for tonight, hopefully I'll get parts ordered tomorrow and maybe start putting things back together after the kids go to bed. Let me know if there is anything else I should to while "I'm in there".

Fun job, isn't. I've more than a few, waiting to be done now. All PM so no big hurry, since S.A.I pump filter has not yet failed in them.

@aging fleet I'd be interested if you found the filter missing or damaged, in your old S.A.I pump replaced back in 2021 and how the current (new 2021 SAI pump) filter looks?
Also what DTC you may have seen before replacement in 2021 if any?
Also any DTC now, that prompt you replacing primary and both secondary S.A.I. switches at this time?
Also pictures of inside (through inlet air port) of each of the 3 old switches?

What I've found is a darker grayish appearance in the inlet side of switches, were filter of S.A.I pump has failed. A cleaner look, in ones filter is intact.

I now use a bore scope, to inspect filter with intake manifold on. Visual inspection, only shows filter is there. It doesn't give indication of condition.

The filter can be recognized be its square corner, seen in back looking through S.A.I pumps air inlet port.

 

[aging fleet]

@2001LC, I replaced the original pump in ‘21 because it was becoming noticeably louder at start and I presumed it wasn't long for this world. I swapped it out before it ever threw a code. I didn’t open the old pump up, but I do remember seeing the filter media intact and nothing looked out of ordinary.

I did throw a code over the winter (early ‘23), want to say it was bank 2 air check valve, but I’m going from memory. My dinosaur of a laptop I used to run Techstream died so I had the code pulled at the parts store. It was temperature dependent so once spring hit, no more DTC.

Old check valves, per your request. Couldn't get a good picture inside the main valve, but it was clean as well.

 

[aging fleet]

Wrapping this whole project up, I got the LC back together this week once my PS vacuum hoses and heater Ts showed up. Man, that intake manifold it a pain to position correctly.

The PS hoses are sold together as an assembly and come with all the clamps which is pretty cool. Below is the old connection point at the manifold vs the new hose.

After replacing the Ts, I reused the original heater hoses and clamps and immediately had a coolant leak once pressure built up. No amount of repositioning of the spring clamps was going to stop it so off to NAPA I went for worm clamps. Not as pretty as the OEM spring clamps, but they stopped the coolant from escaping (used 4 #10s, and 2 #6s). I'll replace all that in about 20,000 miles when the timing belt is due to be changed.

It's now back on the road with no DTCs, leaks, or weird noises.

 

[Get outside]

Or I might end up making worse, we'll find out.

'98-'05 owners, this is the part where you laugh and say, I told you not to buy an '06 or '07 aging fleet. Well, I didn't listen. I wanted the extra horsepower so now it's time for me to pay the vvti tax. I chose not to bypass the system because I'd prefer to have everything work how it's supposed to. That's just a personal preference given replacement parts are readily available, but I totally understand why people choose to bypass the system.

Some background, my '06 has around 153,000 miles and I replaced the air pump back in '21 because it was it was getting noisy and I was afraid it would fail. At that point, I didn't replace the starter or any of the other SAI components. Last winter when the temps dropped below 20 degrees F, I started to throw a DTC because one of the air switching valve was sticking open, or maybe closed, I don't remember. It would resolve itself on longer trips and would stay away until the next cold start.

I ordered parts over the summer and, because it's getting cold again, it's time to cross this project off the list. For anyone that wants to go down this path after me, here are some part numbers. Air pump isn't included (already replaced), but I am doing the starter while I'm in there.

View attachment 3479934

At this point, I've got everything taken apart, but haven't started putting things back together again. The weather should be nice all week so the 40 can do daily duties. I need to order a few parts I wasn't expecting to replace, so far a few brittle cracked hoses and my heater Ts are probably ready after 8 years. I'm hoping to have it all back together in about 5 days.

Some tips so far, you need a top-side creeper or something that will allow you to get on top of the engine to get the intake off and reach all the crap you need to unbolt at the back of the engine. Thanks @Zuberg, for that heads up.

Despite what the FSM said, I didn't drain my coolant and didn't pull the coolant crossover pipe at the back of the engine. It's possible to pull the starter with all that in place, but I did remove the No. 2 air switching valves before attacking the starter. I also removed the bolt holding the electrical connectors on top of the transmission, this made it possible to remove the driver's side starter bolt. Thanks @2001LC for that tip. Once the starter was loose, I was able to turn it counter clockwise and remove the electrical connections.

My creeper.
View attachment 3479976

The current state of affairs
View attachment 3479981

I'm actually not even sure which valve was causing the DTC, but I do know I don't want to pull the intake again so I'm replacing all of it.
View attachment 3479988

That's it for tonight, hopefully I'll get parts ordered tomorrow and maybe start putting things back together after the kids go to bed. Let me know if there is anything else I should to while "I'm in there".

Hello @aging fleet I am Paulo.
While I’m on the middle of chemotherapy treatment I also have this job at my doorsteps. Not fun. But I’m doing the best I can. If you’d rather speak on the phone or text It’d be great too. 805 709 3994
My question for you:
Do you have a list put together with all the part numbers you ended up replacing during the job?
I gathered some of the numbers from the photo you posted here but I know there are some that aren’t shown.
Trying to order all at once if possible.
I have a couple friends helping do the job.
Thank you very much
Paulo

 

[aging fleet]

Hey @Get outside, sorry to hear about the fight with cancer, hope the treatments are successful and finish up soon. My sister starts chemo in a week, so this hits home.

I’m traveling this week, but you should be able to get most of the part numbers you need from this thread with the exception of the secondary air injection pump and the rubber air hoses that connect to it (they’ll be brittle). Since I didn’t remove the coolant cross over pipe, I didn’t need those metal gaskets pictured.

What issue are you having? Knowing that will help us help you with a parts list. Partsouq is where I sourced the majority of what I needed except the starter, their parts diagrams are helpful and it was considerably less expensive than buying domestically. The starter came from my local dealer because the two prior sent by McGeorge Toyota had broken electrical connectors (shipping damage).

 

[2001LC]

A few tips:

• Spend as much time as needed, cleaning top of engine. before, during and after intake manifold R&R. You don't want any dust/sand dropping into intake ports.
• I keep the starter wire housing connector 90980-11400, on-hand. Whenever I plan on starter R&R. Often the old retainer clip breaks off the wire housing.
• It's important, the rubber intake manifold not take a bump against metal during install. It helps to bend the engine lift hooks, outward a little. This makes R&R of intake manifold, just a tad easier.
• Remove the factory filter from the top of S.A.I. pump (blower) and install a replaceable filter.

S.A.I. Modification in VVT engines to prevent its failure! Alert Alert

We've a $2.00 part in the S.A.I.S. of the VVT engine, 1s taking-out ~$7,000.00 $15,000 (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 Land Cruiser & Lexus...

forum.ih8mud.com

 

[Rick Kane]

Hello Aging Fleet. So glad that you posted this project here. I'm trying to replace both of my No. 2 switching valves on my '06 LC100 now, as I'm getting failure codes from both and have registration testing coming up soon. I've got the new valves and have started work on removing the passenger side No. 2 switching valve. Got the short bolts out no problem, but when I started to go to remove the longer bolts I feel a lot of resistance - so much so that I'm worried that I'll break off the bolt heads if I keep going. I tried to shoot some PB Blaster in there, but as the bolt heads are on one side of the No. 2 switching valve and the threads are on the other I'm not sure it really got where it is needed. I'm going to let it sit overnight but was wondering if you also experienced similar resistance with these bolts when you removed your old No. 2 switching valves. Thanks.

 

[2001LC]

When replacing the BK 1 & BK 2 switches. The capture nut/threads, are in switches. So you can just bust the heads/bolts. Get new bolts to go with new gaskets and switches.

You may be able to clear codes, just before getting to test location. Don't turn engine off, while/if in line waiting. You can test if this works, by clearing codes at home, then shut down engine and restart. See how many starts before codes come back.

Having both switches go bad as same times. Indicates other issue(s). If vacuum lines, VSV and electrical circuit of them good. Then the issue is likely upstream. Mostly likely, the S.A.I. filter has failed.

I use a borescope to inspect S.A.I. filter.
If failed, you must take action. Here's what I do:

S.A.I. Modification in VVT engines to prevent its failure! Alert Alert

We've a $2.00 part in the S.A.I.S. of the VVT engine, 1s taking-out ~$7,000.00 $15,000 (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 Land Cruiser & Lexus...

forum.ih8mud.com

 

[Rick Kane]

When replacing the BK 1 & BK 2 switches. The capture nut/threads, are in switches. So you can just bust the heads/bolts. Get new bolts to go with new gaskets and switches.

You may be able to clear codes, just before getting to test location. Don't turn engine off, while/if in line waiting. You can test if this works, by clearing codes at home, then shut down engine and restart. See how many starts before codes come back.

Having both switches go bad as same times. Indicates other issue(s). If vacuum lines, VSV and electrical circuit of them good. Then the issue is likely upstream. Mostly likely, the S.A.I. filter has failed.

I use a borescope to inspect S.A.I. filter.
If failed, you must take action. Here's what I do:

S.A.I. Modification in VVT engines to prevent its failure! Alert Alert

We've a $2.00 part in the S.A.I.S. of the VVT engine, 1s taking-out ~$7,000.00 $15,000 (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 Land Cruiser & Lexus...

forum.ih8mud.com

Thanks much 2001LC. I got new gaskets and switches, but not new bolts (and cannot find the part numbers for those either and am dreading the prices that the local Toyota deal will give me).

In terms of clearing codes, I've done that multiple times, but they pop back almost immediately.

Good point on both switches going bad at the same time and that possibly indicating another issue. I guess I'll see if changing them out works, or if I have to continue to go further up the chain to find the problem. I got all bolts out without breaking them, but stripped the hex head of one pretty well, so I'm off to try to find a replacement. Once I have that, I'll put all back together and see what I get.