FREE INSTANT Air Intake Performance Improvement

[DocJohn]

Since the Injen SRI for the Gen 2 V6 is still 1 to 2 years away from production at last report. I was giving some thought to Swiftoy's idea of modifying the "flapper valve" (more correctly known as "Intake Air Control (IAC) valve #3")

SEE: http://www.zer0.info/solaraguy/viewtopic.php?t=14214

IAC valve #3 which is located in front of the filter box and opens fully to allow air flow when the engine speed is more than 3,200 rpm and the opening angle of the throttle valve is more than 30 degrees.

I've found a FAST, EASY (and totally reverseable) way to re-route the vacuum hoses so that you bypass the Vacuum Switch Valve (VSV) and then IAC #3 (the flapper valve) is ALWAYS fully open at ALL engine speeds. RESULT: less air flow restriction, decreased throttle lag and some improved low-end performance.

I will be posting details in the Gen 2 DIY section on how to do this later today.

[Mole]

sounds interesting.

[got sport]

Looking forward to the update...

[DocJohn]

Here's the DIY info posting...

http://www.zer0.info/solaraguy/viewtopic.php?t=15925

or just go right to the webage I made with the instructions...

http://www.angelfire.com/ky3/gabby/intake_mod.htm

[dvdchris45]

You can just wipe the dirt and dust off with a damp cloth or something if you want to reconnect it to it's original state right?

[DocJohn]

You can just wipe the dirt and dust off with a damp cloth or something if you want to reconnect it to it's original state right?

Right!
I just had the 2 vacuum plugs in my parts box so I used them to plug the ports of the VSV to keep 'em clean. I can't think of any real reason this needs to be done. As you said, you can just wipe 'em off with a damp cloth, reconnect the hoses and you're back to stock in less than 60 seconds.

[sgunitkc]

Is there any downside in doing this?

[dvdchris45]

I got a quick question. How much muscle do you need to use to remove the top part of the brown hose? (the top circle above the VSV #3 circle) I'm scared I might ruin the damn thing but I really wanna give it a try. DocJohn, what do u say? Yank it till it comes off?

[Turbosolara]

lol this system sounds very similiar to AE86/Mr2 4AGE motor's TVIS system. someone should search if anyone done the TVIS modification......

I dont have any knowledge about this dual stage intake valve of the motor, but i am GUESSING if you keep it open, you will result

1. lower mpg
2. run lean at lower end
3. triger a check engine light -> if so, read the code and see what it is

i am wondering why toyota made such system if they can just make #3 open all the time..which is more marketing favorable -> higher power

[DocJohn]

lol this system sounds very similiar to AE86/Mr2 4AGE motor's TVIS system. someone should search if anyone done the TVIS modification......

I dont have any knowledge about this dual stage intake valve of the motor, but i am GUESSING if you keep it open, you will result

1. lower mpg
2. run lean at lower end
3. triger a check engine light -> if so, read the code and see what it is

i am wondering why toyota made such system if they can just make #3 open all the time..which is more marketing favorable -> higher power

The answer is none of the above will or does occur as far as I have seen.
According to the service manual the primary function of this system is to reduce intake noise. With IAC valve #3 open all the time the effective change is similiar to what happens when you install an aftermarket CAI or SRI (but to a lesser degree). The MAF sensor detects the increased air flow and signals the ECU to adjust for it accordingly.
There is no real down side as far as I can see. I'll sacrafice a little more intake noise (and maybe a very slight drop in fuel economy) for the improved throttleresponse. Plus, if you don't like the mod you can go back to the stock set-up in about 30 seconds with no harm done.

[DocJohn]

I got a quick question. How much muscle do you need to use to remove the top part of the brown hose? (the top circle above the VSV #3 circle) I'm scared I might ruin the damn thing but I really wanna give it a try. DocJohn, what do u say? Yank it till it comes off?

The vacuum hoses may be a little tight. Twist (rotate) them a little in both directions while you pull and they should come free.

[drace99]

I will be doing this change today, but I was wondering if you really do notice the differance? Also I was wondering where do you get the 5/16" vacuum hose and plugs? Thanks
Doc

[sgunitkc]

Is this only for the V6 gen 2?

[dvdchris45]

I cant pull the damn thing off. I'd swear its like it has an adhesive on it or something. Maybe with some pliers or something?

Update: I finally pulled it off at the cost of a burnt finger. I took it around the block a few times and noticed the car responds faster at lower revs. We'll see how it does on the freeway. Special thanks to DocJohn for finding such a cool trick up our cars' sleeve. Hope you'll be able to find some more hidden potential in our cars!

[DocJohn]

Is this only for the V6 gen 2?

I really don't know. I'm not going to pretend I know anything about any other Solara. I think the gen 2 I4 has the same intake system but I would have to check the manuals to be sure. If so, this mod will work for you too.

EDIT 3/30/05: I have added some additional info and photo to my DIY webpage for this mod...

http://www.angelfire.com/ky3/gabby/intake_mod.htm