Just want to make sure I'm going to be able to get my motor to idle after removing my IAC and FITV.

 

isnt it controlled on the throttle body?
because thats where you loosen the bolt to change the idle.

 

I believe both valves acts as an air management tool. Much like a wastegate limiting the amount of boost a turbo can run. I don't think you'll have a smooth idle once you remove the IACV, but I'm sure you know that already.

Regards,

Oz

 

you want it to be able to idle after removal of the:

Idle Air Control Valve

yeah, nice one!

good luck!!!!

why are you desiring to remove it anyways?

it doesnt affect performace (unless you remove it!)

t..

 

OK, try this:

expose your throttle body and at idle - plug the ports that are inside the TB next to the throttle plate.

your engine die?

if no, you have a vacuum leak some place

if yes, your IACV is working like it should.

try starting the engine with these holes pluged.

this will allow you to see what these componants do to teh air for idle...

HTH,

t..

 

just found this thread - WOW!

https://honda-tech.com/zerothread?id=337216

the only way you are going to be able to idle is to have hte throttle open some amount all the time...

this can work, but is really for a race only set-up...

t..

 

Leave the IAC and bypass the FITV.... As tinkerbell said the you'll have to crack the throttle plate open a lil if you remove the IAC... otherwise there is no air to idle on... Peace

 

I'm going to try this tomorrow I'm sick of my car stalling!

 

Cool thanks for the reply. I am asking this because of a custom fabricated intake manifold I would like to try out.

What would make leaving the plate open enough to keep an idle a "race only trick"? I'd figure that as long as it idles, thats all that matter, but then again I have yet to try this for myself. TIA

 

Man, what more of a perfect time to see this thread. I just built a new motor and im using the venom sheetmetal intake. I took the FITV and IAC valves off and its a bitch to get the car to idle--right now it jumps up and down between 500 rpm to 900 rpm and just stalls when coming off of any rpm's above 1800. I was thinking about drilling a small hole in the throttle plate, but I dont know if thats the best thing or not.....guess I will have to do some more research.

 

if you can provide for an adjustable stop, then you'll be able to adjust as necessary (1. to dial it in, 2. to change seasons, etc). the idle screws on many bike carbs actually do just that: adjust the throttle opening.

if you can figure what size hole to drill, that'd probably be easier than fabricating an adjustable stop, but it's just not adjustable. too big on the first try will be a mess to fix...

good luck.

dan

 

Well on my LS TB there is an adjustment screw which allows adjustibility to the throttle plates' zero position. Perhaps I should modify this manifold to use the IACV.. How would you hook that up if you had a plenum with runners?

 

ttt

 

Couldn't you just over-tighten the throttle cable so that the throttle is cracked a little all the time?

 

ie a "race only" set up...

t..

 

what is a "plenum with runners"

like ITB's or just the same as all other IM's?
--
the IACV needs one hole into the IM and one drawing filtered air from atmosphere...

and opens itself to allow air into the IM when the ECU thinks it is necessary...

t..

 

This may be a dumb question, but why is an over tightened throtle cable a "race only" set-up? If it was set at 1000rpm idle, whats the problem for the street?

 

sounds so simple!

you could try it and find out?

t..

PS it has something to do with throttle springs, throttle position sensors, cable lenght ratios and vacuum...

 

Ok after reobtaining the manifold I found that I can afterall still use the IACV, everything is intact. However I will be bypassing the FITV.

On this car the IACV has coolant in/out lines that run from the FITV. Will the IACV do its job properly (i.e. make car idle) without having any coolant lines and only the harness connector? TIA

 

THAT was lucky

YES unless it gets below freezing where you are. i am pretty sure that is one of the only reasons for the coolant lines to the IACV (same for the throttle body)

t..

 

I know!!! I was very relieved to find that all the internal plumbing for the IACV had not been affected! Hopefully everything will function just fine without the coolant.

tinkerbell <- this thread's savior!

Do you know how the IACV works? Doesn't the ECU simply proportion how much fresh air gets fed into the plenum? I can't seem to figure out why coolant would have to be involved, unless the FITV depends on the IACV to give the engine even MORE air for extremely cold startups...

 

yes, it uses a solenoid type of plunger that opens a certain amount depending on a signal from the ECU.

this is in response to load events like A/C, P/S, lights, temprature, starting, and closed throttle cruising.

it is electro mechanical and only requires coolant warming to prevent icing of the solenoid.

the FITV has a expanding wax pellet type plunger that slowley expands in relation to coolant temprature, gradually closing the inlet to the plenum, so when it is fully closed it does not supply air to the IM.

the removal of this will only effect idle quality at start-up.

(i always let my engine warm up for 2-3 minutes before driving, and wait till the temp gauge is at least 1/3 before going hard )

t..

 

you are talking about FIV? Fast Idle Valve
well, the FIV uses coolant because it has a thermostat like the engine has, so what it does its that when the engine is cold it makes it idle a lil higher so it would warm up faster, you could remove it, but you have to make sure in the mornings that the car gets warmed up properly.
I have my TB out of my car and i'm contemplating the idea of taking the FIV out, but i'm not sure if i should sacrifice that.
I'm thinking of some idea to create a system that closes the coolant lines after warm up, but some coolant will be stuck there, so i have a lil designing to do. on another note, i don't think that the FIV makes you lose power at all, but that's my opinion.

 

good opinion, the IM gets hot, but not really because of the coolant flowing through it.

it is mostly from the radiated heat passed onto it from the HOT head.

using a phenolic (temprature insulating plastic) gasket will help reduce IM temps and reduce power loss caused by a warm intake charge.

t..

 

so you guys where talking about the FIV??
any way, why would he want to remove it?