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Lexus Owners Club > Lexus Models > Lexus Imports Clubs > Altezza Club
JohnnyTsang
hey guys gave my car a little service putting through new oil, filter, air filter ,gearbox oil and cleaned the maf and throttle body

now i seen this butterfly flap thing inside the airbox but it seems to be permanently raised when car is off and doesnt move when the car is revved up...
the car still hits a kind of v tec when it hits 5k revs tho. how do you keep the flap open permanently?
Monster-Mat
works on vacuum, why do you want to keep it open all the time?
stevie_
i wondered this... i was planning on removing it and it was on my to do list to research it.

*keenly awaits answer from someone who knows it's purpose*
JohnnyTsang
i sure i saw a post saying it gave more of an induction roar at low revs with it unplugged,
but the reason want mine out is it seems to be permantly closed so it must be stoppig some air getting in?
E910
The flap should open at about 4500rpm to let more air in. If you disconnect the vacuum tube it will stay open all the time giving you a bit more induction noise at lower rpm. It's basically a noise suppressor from what I can gather. I have mine disconnected.

[img]http://img228.imageshack.us/img228/199/p10108481rd0.jpg[/img]
stevie_
it's really just there for noise....? right, mine's going
E910
It would seem so.
One guy on the Altezza club did a little test & he reckoned having the flap open all the time increased the mpg a fraction but it's a price I'm willing to pay for a bit of induction noise :winky:

http://www.youtube.com/user/Altezzaeve#p/u/19/AO6dCIFC3_A
JohnnyTsang
so by rights takig it off wil keep it open all the time and increase mpg? boost
Parf
What do you do with the vacuum pipe when you take it off. Do you block it off or leave it open?
stevie_
block it, or you've just introduced a leak into your pcv system. think about it, sucking in unfiltered air is bad.
E910
It doesn't let the air past the filter, that would be pointless. Just more air before the filter. If you have an RS200 then you'll see how it works
Parf
Ive blocked it off now and reset the ECU so it can take into account the extra air flow.
stevie_
[quote name='E910' date='23 July 2010 - 08:26 AM' timestamp='1279873572' post='727344']
It doesn't let the air past the filter, that would be pointless. Just more air before the filter. If you have an RS200 then you'll see how it works
[/quote]


i have an RS200 and i'm fully aware of how it works :whistling:

i presumed that he meant what do you do with the end of the vacuum pipe. having a loose vacuum pipe in your engine is likely to 1. make your car idle like a bag of **** and 2. let air into your pcv system.
E910
There's a solenoid that operates valve the air is feed from the back of the throttle body. Just blank off where the hose connects. It doesn't effect the engines vacuum. As I said if you have a look you'll see how it works
Parf
All done.

Cant say ive noticed more induction noise. I have noticed that you dont get the kick at 5000rpm anymore as the power delivery seems smoother.

Definately worth doing.
stevie_
done here as well - definitely worth doing. i did get an increase in induction noise as well, and much prefer the power delivery - i found it only felt like a kick because it felt like it was being strangled just beforehand. much happier with the power delivery now.
Parf
Maybe I didnt notice the noise because I think my exhaust is on the way out. I get a raspy noise around 3000rpm so there may be something loose.


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