After reading around the internet this morning, I understand a bit better about what you are saying. Due to mine throwing the code after start up, and while driving it IS because of the pressure sensor issue. Pressure sensors may be working fine, but they read no pressure and throw a code. This would be a heck of an opportunity for someone that makes the bypass kits to figure another bypass to trick the sensors when needed. Seems if a person can figure a bypass for the pump and valves, one for the sensors wouldn’t be too difficult, but I’m not the brightest at understanding the computer issues.
Secondary Air Injection Pump Failure on V8's! Important!
- Thread starter Billynath1988
- Start date
After reading around the internet this morning, I understand a bit better about what you are saying. Due to mine throwing the code after start up, and while driving it IS because of the pressure sensor issue. Pressure sensors may be working fine, but they read no pressure and throw a code. This would be a heck of an opportunity for someone that makes the bypass kits to figure another bypass to trick the sensors when needed. Seems if a person can figure a bypass for the pump and valves, one for the sensors wouldn’t be too difficult, but I’m not the brightest at understanding the computer issues.
I dunno....my gut tells me plates will help you. According to darkgun there might be something else due to cold weather....that plates would not help with as he has them installed. It would have to be some weird combination though.....bypasses have been used all over the northern areas of the US, Canada, even have some in Russia! 30degrees ain't nothin' compared to many people that have been using these bypasses. The glitch must be really rare, or Hewitt specific and then yours is actual valve leakage(two different issues).
Just "for fun"
With hood open and looking at the silver 4.7 Toyota fancy cover over the front of the manifold......go back about midway over the manifold then toward the pass side and you will see your pressure sensors.(Brown w black hoses going to them(qty 2)). Make sure those hoses are not cracked......I've had vacuum hoses like that have a crack that caused vacuum leak before. If you want to pull the top hoses off(1 on each sensor)......they should be sucking air if engine is running.(pulling vacuum). The lower one shouldnt have any pressure or vacuum. The top ones are short and go to a metal tube, the bottom ones are longer and loop back around under the manifold and go down by the AIP valves(cant see). I just went to lunch and purposely removed the bottom hoses. No codes.
I came home and then shot some compressed air into the tube for 10 secs or so and also no codes. So not sure exactly how the sensors function....I would think if the air I was shooting in was enough to overcome the vacuum from the top hose maybe it would trip and through codes. I put a pretty good amount of pressure.....but was afraid to put all 110psi into it and damage the sensor. That's got to be how it works though.
So make sure you are not feeling any air from wither of the lower tubes.....if you do, I suspect you have a valve not all the way closed. Might need to get friend to rev up truck to 4K or so and let off gas and see if you feel anything blow out of those hoses.
Just "for fun"
With hood open and looking at the silver 4.7 Toyota fancy cover over the front of the manifold......go back about midway over the manifold then toward the pass side and you will see your pressure sensors.(Brown w black hoses going to them(qty 2)). Make sure those hoses are not cracked......I've had vacuum hoses like that have a crack that caused vacuum leak before. If you want to pull the top hoses off(1 on each sensor)......they should be sucking air if engine is running.(pulling vacuum). The lower one shouldnt have any pressure or vacuum. The top ones are short and go to a metal tube, the bottom ones are longer and loop back around under the manifold and go down by the AIP valves(cant see). I just went to lunch and purposely removed the bottom hoses. No codes.I came home and then shot some compressed air into the tube for 10 secs or so and also no codes. So not sure exactly how the sensors function....I would think if the air I was shooting in was enough to overcome the vacuum from the top hose maybe it would trip and through codes. I put a pretty good amount of pressure.....but was afraid to put all 110psi into it and damage the sensor. That's got to be how it works though.
So make sure you are not feeling any air from wither of the lower tubes.....if you do, I suspect you have a valve not all the way closed. Might need to get friend to rev up truck to 4K or so and let off gas and see if you feel anything blow out of those hoses.
snowboardwcu
Member
i have your kit installed and just got this limpy business and P2445 tonight. i will check out those hoses you mentioned this weekend and report back.
i fear i may have a valve **slightly** stuck open, if thats a thing.
hopefully this just goes away.
snowboardwcu
Member
followup -- been too cold to really do a check -- as far as i can see all the hoses look to be in good shape. no cracks, cuts or anything.
the CEL returned twice since my last post (10 days) but only when it was well below 32F. i was hoping something froze stuck but we had about 2 days of warm weather (up to 60F) so that can't be it.
any other help is appreciated with this one...i'm lost.
the CEL returned twice since my last post (10 days) but only when it was well below 32F. i was hoping something froze stuck but we had about 2 days of warm weather (up to 60F) so that can't be it.
any other help is appreciated with this one...i'm lost.
bendixon89
New member
Simple SAIR fix.. and WTH are y'all complaining about?
Seriously? This is why we can't have nice things..
The design of the SAIR pump and valves are completely different between a tundra/sequoia, and a 4runner/taco.. so that would explain why they didnt (initially) extend the warranty to all designs. As has been said, complaining that a vehicle with 100,000- 150,000 miles having an issue, even a frequent one, is nitpicking at best. I can assure you that Toyota initiates more Limited Service Campaigns (LSC's are model specific non safety related repair campaigns offered free of charge to customers) and more TSB's than any other company.. I can attest to this after being persuaded to initiate a TSB on a noise from the strut mount area on 2016 RAV4s when they were first released...
As a Toyota tech racking up an average of 70 book hours a week - many earned doing SAIR repairs ( and dash pad replacements, another common procedure thanks to a company initiated LSC ** I can say that most dealerships will honor it as a warranty repair, even if its out of warranty... Hence why Toyota is continuously ranked #1 in customer care..
the 4runner warranty program for SAIR issues was extended in November of 2012 to vehicles with 150k.. according to TSB# T-TCI-391 6, with an associated service campaign specifically for US vehicles. Anyways... you could fix it yourself as was previously stated without (usually) replacing any parts.. Here's a bit of help for the more "difficult" set up
Warranty time is like 3-4.5 hours depending on model, but it can typically be done in an hour.. With one of the 4Runner models the valves are on the back of the intake against the firewall and you're instructed to remove the intake.. But honestly, if you remove the 10mm nuts, you can use an E-Torx socket- i believe an E6 or E8, to remove the two studs holding each valve to the intake manifold. By removing the stud, you negate the need to remove the intake, as the valve can now be slid up and out of the vehicle. apply 12v and spray that POS out with some carb cleaner, followed by compressed air. Check the condition of the hoses and vacuum lines, blowing through or replacing any that need it.
**NOTE: totally not tooting my own horn, just distinguishing my "opinions" as more experienced based than someone who tinkers on their vehicle occasionally, though I have respect for the weekend warriors who are passionate about their Yotas. I unfortunately ( I LOVED working for Toyota) left Toyota a year ago to take over my families shop**
Anyways, I dont know about you guys.. But I try to keep the governments hands out of any and everything I can.. Big brother brings nothing but trouble. :bolt: hope this tid bit of info helps.
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Seriously? This is why we can't have nice things..
The design of the SAIR pump and valves are completely different between a tundra/sequoia, and a 4runner/taco.. so that would explain why they didnt (initially) extend the warranty to all designs. As has been said, complaining that a vehicle with 100,000- 150,000 miles having an issue, even a frequent one, is nitpicking at best. I can assure you that Toyota initiates more Limited Service Campaigns (LSC's are model specific non safety related repair campaigns offered free of charge to customers) and more TSB's than any other company.. I can attest to this after being persuaded to initiate a TSB on a noise from the strut mount area on 2016 RAV4s when they were first released...
As a Toyota tech racking up an average of 70 book hours a week - many earned doing SAIR repairs ( and dash pad replacements, another common procedure thanks to a company initiated LSC ** I can say that most dealerships will honor it as a warranty repair, even if its out of warranty... Hence why Toyota is continuously ranked #1 in customer care..
the 4runner warranty program for SAIR issues was extended in November of 2012 to vehicles with 150k.. according to TSB# T-TCI-391 6, with an associated service campaign specifically for US vehicles. Anyways... you could fix it yourself as was previously stated without (usually) replacing any parts.. Here's a bit of help for the more "difficult" set up
Warranty time is like 3-4.5 hours depending on model, but it can typically be done in an hour.. With one of the 4Runner models the valves are on the back of the intake against the firewall and you're instructed to remove the intake.. But honestly, if you remove the 10mm nuts, you can use an E-Torx socket- i believe an E6 or E8, to remove the two studs holding each valve to the intake manifold. By removing the stud, you negate the need to remove the intake, as the valve can now be slid up and out of the vehicle. apply 12v and spray that POS out with some carb cleaner, followed by compressed air. Check the condition of the hoses and vacuum lines, blowing through or replacing any that need it.
**NOTE: totally not tooting my own horn, just distinguishing my "opinions" as more experienced based than someone who tinkers on their vehicle occasionally, though I have respect for the weekend warriors who are passionate about their Yotas. I unfortunately ( I LOVED working for Toyota) left Toyota a year ago to take over my families shop**
Anyways, I dont know about you guys.. But I try to keep the governments hands out of any and everything I can.. Big brother brings nothing but trouble. :bolt: hope this tid bit of info helps.
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Shiftless Joe
Member
Installed the Hewitt bypass as a preventative measure about a month ago, no issues with below zero operation. Good to go.
So beginning last fall, I had the limp mode codes thrown once. Just about every day since then, I would be the ‘noise’ for about 15-20 seconds from the pump when the engine is completely cold at startup.
Just swapped in the Doug Thorley headers. Now I rarely hear the noise when first starting up in the morning. Only hear it after the engine has sat long enough to be completely cold again.
I have not thrown a code since the noise first showed up in the fall. I’m thinking, wiring bypass would be all that is need to correct the problem right?
Sent from my iPhone using Tapatalk
Just swapped in the Doug Thorley headers. Now I rarely hear the noise when first starting up in the morning. Only hear it after the engine has sat long enough to be completely cold again.
I have not thrown a code since the noise first showed up in the fall. I’m thinking, wiring bypass would be all that is need to correct the problem right?
Sent from my iPhone using Tapatalk
BlackWorksInc
New member
[MENTION=211555]bendixon89[/MENTION]
The pumps I think are all actually the same it's the valves that are different for various engines, though I believe all the 2UZ-FE valves are similar in design, I'll have to double check if I ever see a 4Runner/LC100 with failed pumps again. I'm not entirely convinced that's why they didn't initially extend the warranty to those vehicles though. The issue seems to be a faulty intake design for the affected vehicles allowing liquid water (vs. moisture which would be acceptable) into the system and the switching valves and pumps getting corroded. The intake position is still the same on all these vehicles and I don't think I've seen it really designed that much differently on a Tacoma than a 4Runner per say (I also don't see many 1GR-FE units failing either, mostly 3UR-FE & 2UZ-FE Tundras). But the GX470 & LX470 have had a warranty enhancement for these issues for far longer than Toyota did, the vehicle's intake design is similar if not identical (we get a lot of Lexus vehicles at our dealership and have been authorized to do the enhancement on those that have had issues since our closest Lexus dealer is 3 hours away) and Lexus was aware & acknowledging the issue long before Toyota did for thee 4Runner/Landcruiser (similar to how Lexus was aware and covered the driveshaft clunk in the GX470's about a year or two after they released the GX470, yet the 4Runner didn't get the same fix until '12 officially, despite it being the exact same part and exact same failure). Why that is, well I made my opinion on it clear in my older post, but we probably won't know.
I'm still not entirely convinced that Toyota isn't slipping in quality and customer service, but that's an entirely different topic really.
Almost all the pumps I've been doing in the last couple years out here have been corroding inside rather than just getting gunked up. I have a 4.6L 1UR-FE Tundra sitting in my stall for me to rip the pumps and valves out of tomorrow for this very issue.
As for your instructions, spot on; take the studs out and make your life easy (They're E8's on the Tundras so I'd assumed the same on the 4Runner, but it' been a while since I did a 2UZ-FE so they could be E7's or E6's Toyota isn't always consistent on their E-Torx sizes for studs).
Post Note-
I don't entirely disagree with limiting government over-reach, but there's a balance to all things; without some level of government pressure I'm sure none of the Takata airbags or most recalls would ever have been taken care of.
The pumps I think are all actually the same it's the valves that are different for various engines, though I believe all the 2UZ-FE valves are similar in design, I'll have to double check if I ever see a 4Runner/LC100 with failed pumps again. I'm not entirely convinced that's why they didn't initially extend the warranty to those vehicles though. The issue seems to be a faulty intake design for the affected vehicles allowing liquid water (vs. moisture which would be acceptable) into the system and the switching valves and pumps getting corroded. The intake position is still the same on all these vehicles and I don't think I've seen it really designed that much differently on a Tacoma than a 4Runner per say (I also don't see many 1GR-FE units failing either, mostly 3UR-FE & 2UZ-FE Tundras). But the GX470 & LX470 have had a warranty enhancement for these issues for far longer than Toyota did, the vehicle's intake design is similar if not identical (we get a lot of Lexus vehicles at our dealership and have been authorized to do the enhancement on those that have had issues since our closest Lexus dealer is 3 hours away) and Lexus was aware & acknowledging the issue long before Toyota did for thee 4Runner/Landcruiser (similar to how Lexus was aware and covered the driveshaft clunk in the GX470's about a year or two after they released the GX470, yet the 4Runner didn't get the same fix until '12 officially, despite it being the exact same part and exact same failure). Why that is, well I made my opinion on it clear in my older post, but we probably won't know.
I'm still not entirely convinced that Toyota isn't slipping in quality and customer service, but that's an entirely different topic really.
Almost all the pumps I've been doing in the last couple years out here have been corroding inside rather than just getting gunked up. I have a 4.6L 1UR-FE Tundra sitting in my stall for me to rip the pumps and valves out of tomorrow for this very issue.
As for your instructions, spot on; take the studs out and make your life easy (They're E8's on the Tundras so I'd assumed the same on the 4Runner, but it' been a while since I did a 2UZ-FE so they could be E7's or E6's Toyota isn't always consistent on their E-Torx sizes for studs).
Post Note-
I don't entirely disagree with limiting government over-reach, but there's a balance to all things; without some level of government pressure I'm sure none of the Takata airbags or most recalls would ever have been taken care of.
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For the past few months I had a vacuum sound at startup but the other day I got a high pitched dentist drill sound. Only happens on cold start and until the engine warms.
No CEL yet but I have to assume it's the SAIP since I have 150k on my 2005 GX470.
I plan on ordering the bypass from slyfox but should I hold off on driving it until I receive the bypass?
No CEL yet but I have to assume it's the SAIP since I have 150k on my 2005 GX470.
I plan on ordering the bypass from slyfox but should I hold off on driving it until I receive the bypass?
stillflyatl
New member
Bookmarked. I need to by SlyFox Kit.
Thanks again to [MENTION=8828]slyfox75[/MENTION] as his product is a fantastic deal.
I knew my pump was about to go as it started with a mild vacuum noise but then turned into an intense dentist drill noise. Ordered the kit from Jeff (slyfox) and hoped I didn't get a CEL in the meantime. Of course the morning it was delivered I got the dreaded P2440 CEL, valve stuck open with limp mode.
Based on what I saw in this thread and info from Jeff, I was able to get the valve closed, clear the CEL and install the bypass in under 30 minutes. If I had to do it again I could do it in 5 minutes but I purposely went extremely slow so I didn't mess it up.
I now have no CEL, no limp mode, no failing pump and no stuck open valves to worry about.
At $45 you really should just do it proactively. Email [email protected] to buy one
I knew my pump was about to go as it started with a mild vacuum noise but then turned into an intense dentist drill noise. Ordered the kit from Jeff (slyfox) and hoped I didn't get a CEL in the meantime. Of course the morning it was delivered I got the dreaded P2440 CEL, valve stuck open with limp mode.
Based on what I saw in this thread and info from Jeff, I was able to get the valve closed, clear the CEL and install the bypass in under 30 minutes. If I had to do it again I could do it in 5 minutes but I purposely went extremely slow so I didn't mess it up.
I now have no CEL, no limp mode, no failing pump and no stuck open valves to worry about.
At $45 you really should just do it proactively. Email [email protected] to buy one
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Parker1938
Member
I have three Toyotas with the 4.7 V8 and did just that, installed the kits before anything bad happens. Glad to hear you got yours going again.
Parker1938
Member
[MENTION=66389]BlackWorksInc[/MENTION]
I was hoping that the GX460 wasn't going to have this type of problem as I was looking at them for my wife. Are you saying that Lexus has warrantied the repair for these problems in the GX460? If so, do you know the age and mileage limits?
I was hoping that the GX460 wasn't going to have this type of problem as I was looking at them for my wife. Are you saying that Lexus has warrantied the repair for these problems in the GX460? If so, do you know the age and mileage limits?
Yes. And even if you have a valve stuck open, there's a process to get it to close.
It took me reading about 20 pages of comments to find this, but man oh man, as someone who just bought an 03 V8, this is the best news I've heard this week.
BooRad06
New member
Instructions for Slyfox module
I purchased and installed this module about 3 years ago and it worked flawlessly. Unfortunately, some ass hat blew through a stop sign and totalled my 4runner (which I recently replaced with another V8) . I was able to save the module and wiring, but in my haste, I didn't take the time to diagram how it was installed. Is there a set of instructions posted anywhere here? I quickly skimmed through all of the pages but maybe I missed it. I have emailed Jeff, but have not heard back yet. Any help would be greatly appreciated.
I purchased and installed this module about 3 years ago and it worked flawlessly. Unfortunately, some ass hat blew through a stop sign and totalled my 4runner (which I recently replaced with another V8) . I was able to save the module and wiring, but in my haste, I didn't take the time to diagram how it was installed. Is there a set of instructions posted anywhere here? I quickly skimmed through all of the pages but maybe I missed it. I have emailed Jeff, but have not heard back yet. Any help would be greatly appreciated.
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