Dreaded P2447

[grando]

Got the dreaded p2447 code, limp mode also engaged. Typical check engine, flashing 4Lo and trac off lights. To make things even better, was on the way to work! Needless to say, headed home and swapped out the 200 for my 100. ordered the Hewitt Gen II kit and will tackle that next week. Ugh. Truck in a 2011 LX570 with 99k miles

 

[camino70]

They shipped quickly to me and install was easier than I expected. Do you have a code reader that you can clear and get you out of Limp mode?

 

[grando]

I do, any tricks to the install? Just did a bunch of PM then this happened. Didn’t know this was an issue with the 5.7 until I read the Tundraforums!

 

[camino70]

No tricks, it’s straight forward and quick.
take note or take a picture of the bottom of the relay you use for power, so you don’t think you wired something wrong and burned it up in the future.

 

[Reckless]

Got the dreaded p2447 code, limp mode also engaged. Typical check engine, flashing 4Lo and trac off lights. To make things even better, was on the way to work! Needless to say, headed home and swapped out the 200 for my 100. ordered the Hewitt Gen II kit and will tackle that next week. Ugh. Truck in a 2011 LX570 with 99k miles

I havent heard of hewitt gen ii kit, what does it do? I have gotten this issue ~20 times in last 150k miles. Hasnt happened in awhile but wasnt aware there was a solution for it. I would restart vehicle and it would go away.

 

[grando]

The Hewitt bypass kit was made for errors in the emissions system with faulty air induction pumps. They get stuck at times tripping this fault. The Tundra forums have a lot of details. It’s pertinent to Toyota 5.7 engines but Toyota only extended warranty to tundras. To fix it costs 2000-3000, the kit bypasses the whole system. Folks say their trucks still pass emissions too. I am doing it because I went into limp mode. It’s kind of strange that the engineers correlated an emissions system fault to affect the transmission system.

 

[Markuson]

The Hewitt bypass kit was made for errors in the emissions system with faulty air induction pumps. They get stuck at times tripping this fault. The Tundra forums have a lot of details. It’s pertinent to Toyota 5.7 engines but Toyota only extended warranty to tundras. To fix it costs 2000-3000, the kit bypasses the whole system. Folks say their trucks still pass emissions too. I am doing it because I went into limp mode. It’s kind of strange that the engineers correlated an emissions system fault to affect the transmission system.

My understanding through a trusted third party is... A funky side benefit to the Hewitt bypass is it shuts down a potential water ingress disaster that can shove water in the engine (despite a snorkel!) if you happen to be in water when that system intermittently kicks in. I’m looking into doing it for just that reason.

 

[grinchy]

I plumbed the air intake pumps into my snorkel. All right there within a few inches of each other

 

[Markuson]

I plumbed the air intake pumps into my snorkel. All right there within a few inches of each other

Tgats clever.

Seems the function it seeks to cancel is a totally useless EPA thing. I like the idea of just deactivating it. I’m told its badically plug and play simple.

 

[grinchy]

It was about $15 for a couple fittings and some random hose. I guess the AIP is still a risk, but I think far less so.

 

[Markuson]

It was about $15 for a couple fittings and some random hose. I guess the AIP is still a risk, but I think far less so.

Seems like a great candidate for a write up.

 

[CharlieS]

Tgats clever.

Seems the function is totally useless beyond EPA stuff. I like the idea of just deactivating it. I’m told its badically plug and play simple.

If you are talking about the Hewitt Gen 2 bypass, the electrical side is plug and play. It replaces the driver modules, and has a harness that hooks into the (pressure?) sensors at the back of the engine. Unplugging the factory connectors and installing the harness connectors is challenging, but doable (it is a fiddly task in a narrow space between the engine and firewall). There are also block off plates that could be installed between the head and exhaust manifold, but depending upon what in your system failed, you may not need to install them (I didn’t).

Side note, both of my pumps tested out as completely functional, the Slee compressor tray wore through a wire in the harness near the relay modules and fried one of my factory relay modules. I repaired the damage to the harness, and eventually uninstalled the Hewitt kit and put in a replacement set of drivers from a Tundra that fixed the issue.

 

[Markuson]

It was about $15 for a couple fittings and some random hose. I guess the AIP is still a risk, but I think far less so.

If you are talking about the Hewitt Gen 2 bypass, the electrical side is plug and play. It replaces the driver modules, and has a harness that hooks into the (pressure?) sensors at the back of the engine. Unplugging the factory connectors and installing the harness connectors is challenging, but doable (it is a fiddly task in a narrow space between the engine and firewall). There are also block off plates that could be installed between the head and exhaust manifold, but depending upon what in your system failed, you may not need to install them (I didn’t).

Side note, both of my pumps tested out as completely functional, the Slee compressor tray wore through a wire in the harness near the relay modules and fried one of my factory relay modules. I repaired the damage to the harness, and eventually uninstalled the Hewitt kit and put in a replacement set of drivers from a Tundra that fixed the

If you are talking about the Hewitt Gen 2 bypass, the electrical side is plug and play. It replaces the driver modules, and has a harness that hooks into the (pressure?) sensors at the back of the engine. Unplugging the factory connectors and installing the harness connectors is challenging, but doable (it is a fiddly task in a narrow space between the engine and firewall). There are also block off plates that could be installed between the head and exhaust manifold, but depending upon what in your system failed, you may not need to install them (I didn’t).

Side note, both of my pumps tested out as completely functional, the Slee compressor tray wore through a wire in the harness near the relay modules and fried one of my factory relay modules. I repaired the damage to the harness, and eventually uninstalled the Hewitt kit and put in a replacement set of drivers from a Tundra that fixed the issue.

I didnt mean the Hewitt fix was useless. Just that the annoying function it seeks to bypass is pretty useless.

I’m curious to see more detail of what @grinchy did to his. $15 sounds like a winner to me.

 

[grinchy]

I’m curious to see more detail of what @grinchy did to his. $15 sounds like a winner to me.

I disconnected the horns and removed the factory hose from the air pumps. The air pumps are in the right hand front wheel well, behind the wheel liner.
I wandered around Home Depot and eventually found some tube about the same size in the washer dryer section.
Put a couple fittings into the snorkel in the front to connect to. I used double barb, it wasn’t great. Suggest using actual bulkhead fittings, but the principal is the same.
Connect up the tube and now the air pumps won’t drown.
There was one report of a forum user rerouting the air pumps and using smaller diameter and having an issue so make sure to preserve the diameter

 

[boatman]

The Hewitt bypass kit was made for errors in the emissions system with faulty air induction pumps. They get stuck at times tripping this fault. The Tundra forums have a lot of details. It’s pertinent to Toyota 5.7 engines but Toyota only extended warranty to tundras. To fix it costs 2000-3000, the kit bypasses the whole system. Folks say their trucks still pass emissions too. I am doing it because I went into limp mode. It’s kind of strange that the engineers correlated an emissions system fault to affect the transmission system.

I've got a 2013 5.7 Tunda and just experienced the 2447 code. I'm interested in the extended warranty that's been mentioned. Anyone know where i can find it and how many years/miles its good for? Thanks

 

[highfructose]

My understanding through a trusted third party is... A funky side benefit to the Hewitt bypass is it shuts down a potential water ingress disaster that can shove water in the engine (despite a snorkel!) if you happen to be in water when that system intermittently kicks in. I’m looking into doing it for just that reason.

What years have this?

 

[Markuson]

What years have this?

Someone can correct me, but I believe its all 5.7 petrol 200s…

 

[highfructose]

Someone can correct me, but I believe its all 5.7 petrol 200s…

Is it possible to preemptively “turn it off” so it won’t break and place one in limp mode (or inhale water into the engine)?

 

[a200]

Someone can correct me, but I believe its all 5.7 petrol 200s…

The vvti 4.7s all have the same issue too.

 

[lx200inAR]

Someone can correct me, but I believe its all 5.7 petrol 200s…

It's every vehicle Toyota has put SAIS on from what I understand. So all the V8s starting around 2005, and I believe there are V6s that have same issue. Quickly checking the website, they sell kits for 2.7, 4.0, 4.6, 4.7, and 5.7 motors.

Is it possible to preemptively “turn it off” so it won’t break and place one in limp mode (or inhale water into the engine)?

Many people use the bypass kit preemptively.