4agze vsv bleed/bypass

[bassy]

hi all, i am currently in the process of completing my 4agze ke30, however i am missing a few things such as mag sensor, vsv bleed and bypass valve, diagnostics and a few other things.
anyway, i was wondering if i need to use the vsv bleed and vsv bypass . i have removed the abv.
i have searched this and found that one controls the pressure in the sc, varying when boost is on. And was told it is mostly imissions control. if any of this is wrong please correct me.

If anyone has any specific information that would be great.

bassy

[mojo_type]

it regulates the boost so it comes on low psi at low rpm and higher 7-8psi near 6,000 rpm

i bypassed mine but still have my abv in place

others that have removed the abv have also removed the vsv's

so in other words yeah u need em for the abv and if you have removed it then as far as i know
you dont need them

[bassy]

well thats a start, thanks mojo. what is going to happen to the computer if these devices arent plugged in, will it even be able to detect weather it there?

"it regulates the boost so it comes on low psi at low rpm and higher 7-8psi near 6,000 rpm"

not sure what you are refering to there though mojo. what is regulating this? i thought boost will rise as the revs climb anyway. thats how sc's work.

[mojo_type]

vsvs limit the boost somehow

not exactly sure how or the technicals but say 3-4grand it would go 4psi and wind it out to
7 grand and it would hit 8psi

bypass them and it goes prety much to 7psi at 3 grand then peaks at 9-10 psi at 5grand

[feral4mr2]

anyway, i was wondering if i need to use the vsv bleed and vsv bypass . i have removed the abv.

please explain what you mean by the vsv bleed? vsv bypass i assume you are talking about the blue one that controls the ABV?

it regulates the boost so it comes on low psi at low rpm and higher 7-8psi near 6,000 rpm

there is no such thing as a vsv (which is a vaucum switching valve) that limits boost at low to more at higher rpm. there is a blue vsv mounted low on the s/c that the ECU controls to open the ABV at idle and when it reaches ~8psi.

bypass them and it goes prety much to 7psi at 3 grand then peaks at 9-10 psi at 5grand

boost level is controled by the size of the crank pulley, not a vsv.

[The Witzl]

Basically, the VSV Bleed and VSV Bypass are not essential. They are for emissions crap and the car will work fine without them, and the ECU would never know!

.... also, I have a 4A-GZE Map sensor for sale if you need it.

Here's some useful tech info for you, courtesy of my good self and Puzzleman

[feral4mr2]

what vsv is the dude going to not use? the only vsv i can think of that he doesnt need is the blue one that operates the ABV as he has removed it. he still needs the fuel pressure reg vsv, what other one is he talking about? vsv bleed? wtf is that?
(i know i have only worked on the AFM 4agze, how many other vsv's are there on a MAP version?).

[Draven]

oh karl, +rep for the ultimate backyard diagram

[bassy]

witzl, you just made my life a whole lot easy. that pretty much answers my question. +rep for you, and thanks to everyone else who contributed.

feralmr2 this is the vaccum plate that is on the ae92. sorry i dont have a pic of the vsv's as i dont have them.


well im gonna not run them and see how i go, if anyone thinks this could be bad idea please let me knoe asap.

thanks again people

[feral4mr2]

got that AFM vacum diagram. i am wanting to know what a vsv bleed is?

[Timma]

just confirming, u dont need the bvsv or vsv right?

[The Witzl]

I've read somewhere where someone was seeing what difference having the (brown) FPU vsv connected or not did - and it made little difference apparently.
From memory all it did was adjust the fuel pressure marginally at certain times to get either better fuel economy or emissions...... and in the real world (ie Toymods) this is not important.

When i did my 4A-GTE using an AE92 4A-GZE ecu, i never had ANY of these vsv's, and I had no issues related to them.


To be honest, you really dont need any of them.

• FPU - fuel pressure related. not essential
• VSV2 - for emissions purposes only. keeps vacuum to the charcoal can more regulated
• VSV3 - the ABV controller.

Then you have the bigger idle up valve. I recommend keeping this one as it ups the idle when you turn on things like Aircon etc.

[Timma]

Thanks witzl! I'm running my 2vzfe without the bvsv and hasn't changed anything.