P1444/P1445 - Secondary Air Injection System (1 Viewer)
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ewillis
SILVER Star
Just ordered a Hewitt bypass as I'm getting the shop vac sound on startup after sitting for awhile. No codes or limp mode. 25% off...today is the last day for the sale. Hewitt-Tech SAIS Bypass Kits - Store
2001LC
SILVER Star
Just a note about the PO1444 & PO1445. These are secondary bank 1 (1444) and bank 2 (1445) codes.
These are the switch on rear water by pass joint in VVT engines (may 2005- June 2007 100 series) stuck close. Getting both "may" indicate a problem that requires removing intake manifold, just one code would likely not. As it is possibly to R&R secondary bk 1 or 2 switch from back without (see second picture in OP). If stuck closed a CEL comes on, but no harm. It's more or less a block off at that point. It may be switch, vacuum line, VSV, wires or ECM.
These can also have moisture in them. In that event, it may only stick when OAT below freezing. This may take care of itself in time.
If however stuck open (different code), it does need addressing. This allows gasses to flow back into main switch. Basically an exhaust leak.
These are the switch on rear water by pass joint in VVT engines (may 2005- June 2007 100 series) stuck close. Getting both "may" indicate a problem that requires removing intake manifold, just one code would likely not. As it is possibly to R&R secondary bk 1 or 2 switch from back without (see second picture in OP). If stuck closed a CEL comes on, but no harm. It's more or less a block off at that point. It may be switch, vacuum line, VSV, wires or ECM.
These can also have moisture in them. In that event, it may only stick when OAT below freezing. This may take care of itself in time.
If however stuck open (different code), it does need addressing. This allows gasses to flow back into main switch. Basically an exhaust leak.
So can this Hewitt bypass kit fix a system that's already failed? Like if the valves are stuck open?
hewitttech
SAIS Bypass Kit
Not getting notifications from the site so sorry for the slow response.
The bypass kits are sold for off road use or exempt use only. Even though the system may have already failed it is against federal emissions and CARB rules to prevent the system from running or otherwise make an emissions system inoperable. What you decide to do with it is however entirely up to you. That being said, as long as you don't have any other issues, CEL, trouble codes etc. and you go through enough drive cycles to set all of your other emissions monitors getting an exempt vehicle to pass smog is not a problem.
Yes, that is pretty much the main purpose of the bypass kit, so you don't have to replace all the compenents of the system to turn of the CEL and get out of limp mode. I do not know where the idea came from that the system has to be operating for the bypass kit to work but I suppose it is from the other knockoffs that don't have a solution for all the trouble codes like we do. Check out this link to our codes page for a better understanding: Hewitt Tech Codes Page - Addons Explanations
For the 2 kits shown, I don't see 2008 GX470 listed in either pop down menu. Is there a reason for that? Thanks
hewitttech
SAIS Bypass Kit
Not sure which two listings you are looking at but yes, our listings are broken up by coverage.
The 08 GX470 is only going to be found under our Gen-I V54H kits for the 08-12/13 vehicles and our Gen-II-3V kits for most of the 4.7L vehicles is under that listing separate of the normal Gen-II kits. We separate what we call the 3 valve 4.7L vehicles from the Gen-II because on those vehicels all of the secondary air system is located underneath the intake manifold and require 3 soldered connections to the ECM since there is no way to connect to the pressure sensor without removing the intake manifold. If you have any other questions please give us a call Toll Free 1-844-307-7671
Thanks! I was just looking at one of the links posted earlier.
I have P1445 code on a 2005 GX470.
Is the “switch” you mention the same as the “valve”?
Anyone have experience troubleshooting vacuum line, VSV (??), wires or ECM? Are there more advanced OBD2 or other scanners that can point one towards something other than the “switch”?
While I understand that a closed valve is not a problem (and likely advantageous), can one pass a DEQ smog check in Oregon with CEL on and P1445 code?
Also, while closed valve may not be a problem, on my rig when CEL is triggered VSC/TRAC, VSC/OFF and Anti-Slip dash lights are illuminated - I assume that illumination means that those systems are deactivated?
Thanks
For a 2005 GX470 with just the P1445 code, which kit is recommended to prevent CEL and code as well as showing that all systems are “ready”.
Given the reported challenges of accessing the switching valves on a 2005 GX470, how challenging/ is it possible to install your bypass plates on this rig?
2001LC
SILVER Star
First I'll say: I'd use bore scope to check on the S.A.I. pumps (blowers) filter. Which pump, is under front of intake manifold. That said:
YES "switch" (SW) = switching valve.
When we look in the FSM repair section. It states: Switching Valve (main SW under intake manifold connected (downstream of blower (pump)) with 1" ID hose and has air sensor attached to it (main switch valve), then a 1" ID hose connects (down stream) it (main SW valve) to rear water bypass joint which has two Switching Valves: SW valve No. 1 (BK1, driver side (DS)) attached to rear water bypass joint And Switching Valve No 2 (BK2, PS) attached to rear water bypass joint.
A TSB states we must replace all parts of the S.A.I. with this code. What I've found happens most times, is dust clogs the air sensor orifice, which on main switching valve. The dust entered all 3 valves (AKA SW, AKA SW Valves), due to failure of the foam filter in pump (blower motor housing). Once filter gone, dust blows into all SWs and throughout the entire system.
There are two VSV ( vacuum SW valves) on passenger side (PS) of intake manifold. A small vacuum line comes from front underside of intake manifold to them. Each VSV has a wire to it from ECM and a vacuum line. Each small VSV vacuum line, goes to back area of intake manifold to it's (SW No1 - SW No2) SW Valve on rear water bypass joint. We test these VSV, both by jumping with 12v and with vacuum hand pump tester.
Here you'll see picture and explanation, which will show locations of components (pump & SWs).
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
Asking; "Can you pass emission test" NO!
Federal LAW: You can NOT disable a vehicles emission nor modify it, unless such modification maintains emissions reduction as vehicle manufacture designed or further reduce emissions (improves). Above link, gives a simple solution to improve the system. Not that it further reduces emission, but results in system working as design for the long term. I've been running a test for 5 years now on this simple replaceable (takes 3 second to replace filter, once mod done) filter modification. It works flawlessly.
You can cheat on a test, to pass a test. But does it make it okay!
Some people are of a mind, that: If they can get away with a crime, it's okay to commit the crime.
I'm a polluter, driving V8's all my life. But, I work to keep engine/vehicle running at peak, including all pollution system.
Vehicle Pollution Systems do make a difference. Even the 90 seconds the S.A.I. system runs, helps reduce pollution.
Hewitt block off kits. Are for off road use only. Unless you trailer your rig to off road location, never drive on a public road, street or HWY. They are not legal!
I get some asking me to install a S.A.I. block off kit. I will not!.
Most 100 series, I see with some sort of block off. Have issues them. I will not help correct the issue(s) it causes. I will recommend removing and going back to stock design.
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hewitttech
SAIS Bypass Kit
On any of the vehicles to get the system to show ready/complete you would need to use the Gen2 kits. On the 2005-2009 GX470 and LX470 vehicles you would be using a special version of the Gen2 kit, the Gen2-3V. The Gen2 kits need to connect into the system's pressure sensors. The problem with what we call the 3-Valve vehicles where the entire system is located underneath the intake manifold is there is no way to easily connect to this sensor. Because of that the Gen2-3V has an additional harness whip that must be routed to the ECM where these three wires need to be professionally spliced into the sensor wires directly. If you have any other questions please contact us directly by phone, email or our contact us page.
Toll Free 1-844-307-7671
Support@hewitt-tech.com
Hewitt Technologies | Contact Us
Hewitt is here to help! Contact Us for Secondary Air Injections System Bypass kits for Toyota/Lexus Trucks and SUVs. You could save up to $4000 on repairs!
hewitt-tech.com
Yes, Hewitt Technology’s SAIS Bypass Kits and products are sold for off-road, competition or other emissions exempt vehicles only. It is illegal to remove, dismantle or otherwise cause to be inoperative any pollution control device required by federal, state, or local emissions law. . No other applications are intended or implied. By installing or using this SAIS Bypass Kit the vehicle owner and installer acknowledge and assumes ALL risks associated with its use.
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Thanks. Sorry that I did not find your earlier post on topic that is very comprehensive and has great pictures. Too bad for all of us that the intake manifold (and the time it takes to remove and reinstall) makes systematic testing/troubleshooting problematic for most DIYers and mechanics which results in folks replacing more parts than they probably need.First I'll say: I'd use bore scope to check on the S.A.I. pumps (blowers) filter. Which pump, is under front of intake manifold. That said:
YES "switch" (SW) = switching valve.
When we look in the FSM repair section. It states: Switching Valve (main SW under intake manifold connected (downstream of blower (pump)) with 1" ID hose and has air sensor attached to it (main switch valve), then a 1" ID hose connects (down stream) it (main SW valve) to rear water bypass joint which has two Switching Valves: SW valve No. 1 (BK1, driver side (DS)) attached to rear water bypass joint And Switching Valve No 2 (BK2, PS) attached to rear water bypass joint.
A TSB states we must replace all parts of the S.A.I. with this code. What I've found happens most times, is dust clogs the air sensor orifice, which on main switching valve. The dust entered all 3 valves (AKA SW, AKA SW Valves), due to failure of the foam filter in pump (blower motor housing). Once filter gone, dust blows into all SWs and throughout the entire system.
There are two VSV ( vacuum SW valves) on passenger side (PS) of intake manifold. A small vacuum line comes from front underside of intake manifold to them. Each VSV has a wire to it from ECM and a vacuum line. Each small VSV vacuum line, goes to back area of intake manifold to it's (SW No1 - SW No2) SW Valve on rear water bypass joint. We test these VSV, both by jumping with 12v and with vacuum hand pump tester.
Here you'll see picture and explanation, which will show locations of components (pump & SWs).
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...
Asking; "Can you pass emission test" NO!
Federal LAW: You can NOT disable a vehicles emission nor modify it, unless such modification maintains emissions reduction as vehicle manufacture designed or further reduce emissions (improves). Above link, gives a simple solution to improve the system. Not that it further reduces emission, but results in system working as design for the long term. I've been running a test for 5 years now on this simple replaceable (takes 3 second to replace filter, once mod done) filter modification. It works flawlessly.
You can cheat on a test, to pass a test. But does it make it okay!
Some people are of a mind, that: If they can get away with a crime, it's okay to commit the crime.
I'm a polluter, driving V8's all my life. But, I work to keep engine/vehicle running at peak, including all pollution system.
Vehicle Pollution Systems do make a difference. Even the 90 seconds the S.A.I. system runs, helps reduce pollution.
Hewitt block off kits. Are for off road use only. Unless you trailer your rig to off road location, never drive on a public road, street or HWY. They are not legal!
I get some asking me to install a S.A.I. block off kit. I will not!.
Most 100 series, I see with some sort of block off. Have issues them. I will not help correct the issue(s) it causes. I will recommend removing and going back to stock design.
Anyone know a mechanic in Portland, OR area who is a master of the SAIS on a 2005 GX470?
2001LC
SILVER Star
It's
DIY. Takes 6 to 8 hrs.We sometime replace starter while in there. Added benefit, the intake and throttle body rubber (VVTi only) gaskets are replaced. These gaskets, being rubber, shrink with age. So need replacing once in awhile anyway.
Sorry, I can't recommended anyone in Portland. You'll not likely find any shop, to install a block off kit. Doing so opens them up to, a $20K fine and possible jail time. They can even loss their business license in some cities.
Block offs. Also, contribute to global warming
We drive V8s gas hogs. As such need to keep our engine running at peak. To keep our rather large carbon footprint, at least, to design spec.
If you came to me, with P1445, and I worked on GX, which I do not.
The P1445, points to No 2 switch valve (No 2 SW). This is the No 2 SW, that is bolted on the rear water bypass joint on passenger side (BK2). I'd glance over the SW, it's gaskets, vacuum line & VSV. As I pulled the air tube/filter box, to get out of my way. So I could borescope the S.A.I. pumps (blower). To see if filter is there or not, as I mentioned.
If filter no longer in place. I'd proceed with my S.A.I. replaceable filter mod. I'd also very likely (saves redoing the job), replace the main SW valve. It has the air pressure sensor attached to it. The cost of SW w/air sensor, is almost the same as just air sensor alone. I'd NOT likely replace the No. 2 SW, as I can get to it, with intake manifold on at later date. If No 2 sw bad, it's from dust blowing in. So if it's bad, the No.1 SW is in same condition also. But I've found these No.1 & No. 2 SW's rarely need replacing.
If filter is still in place. I do a series of test on the No.2 SW, it's VSV and test Air pressure sensor at ECM wire block. I have found where these SW's have been replaced or removed before. Than later, they give a DTC (P1445 BK2 or P1442 BK1). Because they were not properly installed, resulting in leaks.
A Toyota/Lexus Dealership:
They're likely to say; replace the BK 2 SW and or all S.A.I. components (TSB).
Unless you get a mechanic that actually understands the system and why Lexus did a recalled on the newer (our 4.7L 2UZ VVti not included in recall
) GX460 201-2013 for S.A.I. filter failure. Which is this same filter we have failing, and my mod corrects. Which, my mod, makes a permanent fix w/replaceable filter.Unfortunately the Toyota/lexus fix, is not permanent. Since if they replace S.A.I. pump with same pump we have, which filter will fail again.
In a TSB. Toyota stated, they didn't know why the filter was disintegrating, but suspected moisture played a roll. As did we in mud. I now have a better handle on why filter fails. Filters is getting clogged, which increase pressure of suction on it. It's also shrinking. I've found moisture can have some affect as does extreme (very high and or LOW temperatures) weather. The filter then, gets suck into impeller of pump, and ground up. As the hard dust filled face area of filter, is ground by fins of pump impeller. The fins may also get damaged. To much damaged, may, reduce air flow pressure to point we get DTC. But luckily, not often bad enough to kick off DTC. But some S.A.I. pump, do need to be replaced. Dust then blows throughout the system, resulting in possible additional issue with valves. This is why Toyota TSB recommends all parts be replaced. But I found, the air sensors is the one that caused these DTC (codes), in most. But it will test as good, at ECM voltage test.
I probably understand the issue with these system better than anyone. Why! Because I took the time to find, why the S.A.I system was failed. I did this, looking for why the CAT on the 4.7L VVti were failing, being replaced and failing again. Which lead me to the this little tiny S.A.I pump filter.
I suggest you:
Hire most any mechanic to borescope your S.A.I. pump filter, as a first step. Cost $50 to $100.
Or buy a borescope and DIY inspecting S.A.I. pump filter:
Borescope on Amazon range between $20 and $2,000. In the $100 range, they've high definition and directional control. My $500, 6mm diameter lense borescope, attach to my iphone and is 360 degree directional. It is, difficult to turn back and see into 1" tube on top of air pump, but doable! I'm planning on get yet another borescope. The 8mm lense has better resolution, so may get it. I'd also get one with semi rigid ~3 foot snake and 180 degree directional. I think, it would be easier to navigate to see back into S.A.I. pumps 1" air intake tube. These are in the $100 -$200 range without or with LCD screen. Even the $20 semi rigid snake camera will do the job.
I put out all this info, for you and others that will have same issues and come to this thread..... By gaining this knowledge. You can do the job. Or at least help any good shop, understand what's needed and how should be done for a permanent fix.
Good luck!
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