Not in my Manual

WTH am I looking at folks? (The thing with the big “H”?)

I have been combing through my owners manual trying to figure out what this knob is for. It doesn’t appear on any of the diagrams that I could find.

Here I have pried off the plastic cover. It appears that there was a label glued to the knob at one time and it has fallen loose.

I first I thought it was a heater control valve because there’s a big H on top of the cover.

But IMO this is not a knob: it’s just a cover for an adjustment screw, and it spins freely. At least that’s my theory because I have not tried to break it off yet.

Anyhow it appears to have one hose that leads to this check valve (?) And then to a small rubber manifold that connects to two (air) valves.

 

That's the SAIS, or secondary air injection system. It's some emissions thing. That "knob" is an air filter.

https://www.youtube.com/watch?v=XO5d4MqZu5I

 

https://www.tacomaworld.com/threads/2012-wont-accelerate.389739/#post-17799397

Post 13.

You have the 'favored' year.

 

OK, thank you guys. This is just a big expensive air bleed.

I took it into the dealer for the service last year on this under warranty, as there was a service bulletin.

This is the bit with a little sponge filter that degrades under wet weather and then plugs up.

Fortunately I live in the desert and I only wash my truck infrequently because of the drought, so just never turned out to be a problem.

 

Not exactly.

'water' is not the issue, but when the system fails the truck will set a code, sometimes failing to run. Or at least run well.

It's not a recall, but it does have an extended warranty so if it fails you'll be covered based on the link provided.

2012 was the worst year for this device to fail.

Many of us have replaced the filter with a small pleated filter to preclude the problem.

 

I don't know how I butchered the title on this thread, but I was on the cell phone...
Anyhow the dealer has supposedly replaced that filter due to a service bulletin.
But I should check it myself.

 

OK, my truck has 50k miles, and my filter was clean, so it's just been replaced. The snail was clean inside too. No evidence of dust/degradation.

My truck has never missed a beat since I bought it 5 years ago with 32k miles on the clock, but I took it in immediately after the bulletin arrived from Toyota. Mine mentioned moisture getting into the switching valves.

 

In what way worst? So many failed? or the failures caused so much damage?

(I wonder if they changed the filter formula in 2013?)

Well it's all moot, thanks, since mine didn't fail, and I will add the filter mod to my shopping list.

 

The earlier models with SAIS had slightly more trouble with the valves because the later models (somewhere around 13 and 14) added programming to run the pump and open the valves for a couple seconds at engine shutown to purge the moisture from the system.
Filter design seems to be the same but the later models weren't part of the TSB.
I've done the UNI filter mod on mine just to rule out the filter as a possible failure point but the pumps and valves are know failure points too especially on earlier models it seems.

 

it's how to charge $35k for a sub-$18k truck

 

Unfortunately SAIS is an emissions item so you can blame your government and EPA for that one, vehicle manufacturers have to meet emissions, fuel mileage, and safety standards if they want to sell vehicles here and it just gets worse every year.

On the bright side our trucks do have about the best resale value in the industry.

 

It's an air pump that pumps air into the exhaust to heat up the converters faster. The faster the converters heat up, the faster they can start working as designed

The problem toyota had was the foam filter would break into pieces, go down the line and clog up the valves that regulate the flow of air into the exhaust

I haven't done any debris related repairs on Tacomas but I've done a few on v8 Tundras

 

Thank you fellows, and everybody gets a like today for their kind participation.

So far my only problem with the pre-runner has been the fact that it’s just jacked up so high that it wrecks the ball joints and tie rod ends when you go over big bumps. The wheelbearings ain’t nothing special either.

Of course like a dummy I lifted the truck 2 inches above stock. I don’t know why I thought I would like it better. I definitely plan to lower this truck again.

I have taken this truck on a dirt road exactly 2 times since I bought it. You can eat off of my undercarriage it is so clean.

I probably should’ve bought the city model with the low suspension and all the ground effects crap. The X-runner?

Now I wonder how the suspension and bearings are holding out on those models?

 

I guess that's why my wifes Tacoma built 4/2013 sounds weird every time you shut it off. That pump purging moisture. I've read about the failures of that sponge element here at TWso I went and purchased the unifilter. When I took it apart to do the mod there was absolutely no evidence of degrading so I left it as it.

 

My wifes 2012. Always scared when I wash the motor.

 

Uni mod on my 13 - almost 3 years no problems & keep your factory shit incase it goes out

 

I left the top cover on mine for that reason but moisture shouldn't hurt it as long as it doesn't sit in there thus the reason for the shutdown purge on newer models.

 

Top cover is on mine with the uni mod. You can leave it off but you’ll have to replace it faster. Def don’t wash the engine with the uni filter exposed

 

Thank you all, and once again everybody gets a like. And if you look under your seat you’ll find a free Unifilter!

What no?….oh crap….I guess the 0prah people got in here first.

 

I know if you get too much water in there and the fan kicks on the blades can get destroyed.