Idle Air Control Valve HELP!!!

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tuner2484

New Member
I have a 91 integra and just purchased a bdl throttle body and Edelbrock intake manifold....the only problem is that i have no idea how to connect the IACV on the new intake. It has 2 ports. I already connected the harness and installed it I just have no idea where i should connect both ends. Do you connect both ends to vacuum or what? The instructions on edelbrocks page don't tell you anything about how to connect the IACV. If anyone knows how to connect it I will surely appreciate it.
 
I could be wrong but I believe its simply bolted in with 2 bolts, with 2 vaccum lines that run your coolant and the harness
 
its not vaccum, its coolant.

one should go at or around your intake mani by the T-stat housing.. and the other hose will go onto your solid pipe that takes coolant from the water pump, to the housing.. its on the back of the block. there should be a nipple on that solid hose..
 
yeah. just dont hook up the coolant lines. by pass it. the coolant doesnt do anything but help heat it up in the winter and cool it down in the summer.
 
you can, but i think its stupid.. your idle will most likey be very irratic if you dont have the car tuned. (by having the ECU depend on another sensor to conrol idle)...and you cant just unhook coolant lines, you must get a plate.. that will bolt over the holes..

and thats not at all what a IACV does.. it uses coolant, to read the temp of the engine, just like the Fast idle thermo valve(fitv) does, when its cold, the vavle opens, letting more air in during cold starts/warm up. and when the coolant gets hot, the IACV reads this, and closes that valve. reducing air flow pass the butterfly. thus you get your high idle when cold, and your lower idle when warm.. your FITV does 75% of your cold starting idle when its there on your TB. some cars do no have a FITV, so 100% of cold idle is done by your IACV.
 
you can, but i think its stupid.. your idle will most likey be very irratic if you dont have the car tuned. (by having the ECU depend on another sensor to conrol idle)...and you cant just unhook coolant lines, you must get a plate.. that will bolt over the holes..

and thats not at all what a IACV does.. it uses coolant, to read the temp of the engine, just like the Fast idle thermo valve(fitv) does, when its cold, the vavle opens, letting more air in during cold starts/warm up. and when the coolant gets hot, the IACV reads this, and closes that valve. reducing air flow pass the butterfly. thus you get your high idle when cold, and your lower idle when warm.. your FITV does 75% of your cold starting idle when its there on your TB. some cars do no have a FITV, so 100% of cold idle is done by your IACV.

post your source. :)

i say your wrong.

the idle will not get more erratic without coolant lines going to the IACV. a tune has nothing to do with that.

you dont need any sort of plate. no block off plate. it's only coolant used to warm it up in the winter (keeps it from sticking), and cool it down in the summer (to keep it from overheating). the coolant has NO effect on the IACV's overall functionality.

the ECU reads the engine speed and electronic load detector, and then adjusts the IACV accordingly, to raise, or lower the idle.

there is NO thermostat in the IACV.

the FITV has a wax plunger in it that reacts to heat and expands to close a completely different air bypass hole. those cars without the FITV, rely on the ECU to read the engine speed and the thermostat and then adjust the IACV load to bring the rpm up accordingly.

-> are you sure you knew what you are talking about here? dont spread information you dont know 100%. gets people all confuzzled.
 
People, please do not give out information if it is not correct. The valve you are all speaking of is NOT the IACV. It is the FITV (fast idle thermal valve). One coolant line in and one coolant line out. IF you try to bypass it, your engine will idle very erratically and will become an annoyance. Your IACV is electronically controlled and vacuum controlled. The IACV is located at the 'rear' of the intake manifold. The two lines are vacuum lines to the manifold. The FITV is located underneath the throttle body and has one coolant line in and one line back to a nipple on the water neck.

EDIT: You have the wrong idea on how the iacv works as well as the fitv. Coolant flows through the fitv over a plunger. When the coolant temp. starts to warm the plunger starts to close, thus bringing your idle down. The fitv is there mainly to hold your idle up until the engine reaches normal operating temperature. From there, the IACV takes over.
 
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People, please do not give out information if it is not correct. The valve you are all speaking of is NOT the IACV. It is the FITV (fast idle thermal valve). One coolant line in and one coolant line out. IF you try to bypass it, your engine will idle very erratically and will become an annoyance. Your IACV is electronically controlled and vacuum controlled. The IACV is located at the 'rear' of the intake manifold. The two lines are vacuum lines to the manifold. The FITV is located underneath the throttle body and has one coolant line in and one line back to a nipple on the water neck.

EDIT: You have the wrong idea on how the iacv works as well as the fitv. Coolant flows through the fitv over a plunger. When the coolant temp. starts to warm the plunger starts to close, thus bringing your idle down. The fitv is there mainly to hold your idle up until the engine reaches normal operating temperature. From there, the IACV takes over.

nice timing, i didnt even see your post. u were talking to him, i assume?
 
This is directed to whoever has a mis-conception on how these parts actually work. :)
 
It is the FITV (fast idle thermal valve). One coolant line in and one coolant line out. -yes

IF you try to bypass it, your engine will idle very erratically and will become an annoyance.-no, mine is bypassed, i dont have a problem.

Your IACV is electronically controlled and vacuum controlled.-nope, sure isnt.

The IACV is located at the 'rear' of the intake manifold.-yes

The two lines are vacuum lines to the manifold.-nope

The FITV is located underneath the throttle body and has one coolant line in and one line back to a nipple on the water neck.-yes it is, and yes it does.

EDIT: You have the wrong idea on how the iacv works as well as the fitv.-nope, sure dont.

Coolant flows through the fitv over a plunger. When the coolant temp. starts to warm the plunger starts to close, thus bringing your idle down.-yes it does

The fitv is there mainly to hold your idle up until the engine reaches normal operating temperature.-yes it does.

From there, the IACV takes over.-exactly my point.


[bold/underline = ME!]
 
It is the FITV (fast idle thermal valve). One coolant line in and one coolant line out. -yes

IF you try to bypass it, your engine will idle very erratically and will become an annoyance.-no, mine is bypassed, i dont have a problem.
Than what holds your idle up when your engine is cold?

Your IACV is electronically controlled and vacuum controlled.-nope, sure isnt.
So I guess those wires going into a harness clip are just there for show?

The IACV is located at the 'rear' of the intake manifold.-yes

The two lines are vacuum lines to the manifold.-nope

The FITV is located underneath the throttle body and has one coolant line in and one line back to a nipple on the water neck.-yes it is, and yes it does.

EDIT: You have the wrong idea on how the iacv works as well as the fitv.-nope, sure dont.

Coolant flows through the fitv over a plunger. When the coolant temp. starts to warm the plunger starts to close, thus bringing your idle down.-yes it does

The fitv is there mainly to hold your idle up until the engine reaches normal operating temperature.-yes it does.

From there, the IACV takes over.-exactly my point.


[bold/underline = ME!]


Do me a favor and just keep your nonsense to yourself. You obviously know nothing about these valves. Do I have to open up ALLDATA and make you look stupid infront of the HS community?
 
also, my idle at cold, goes to about 1600 or so, then steadily drops off from there as temp rises.

and another thing, i ment that the IACV IS NOT HOOKED UP TO VACCUM LINES.. one more time, incase your not hearing me correctly

THE TWO HOSES, ON THE BOTTOM OF THE IACV, ARE NOT HOOKED TO VACCUM, THEY ARE HOOKED TO COOLANT.
 
In 1988 Honda added an IAC valve to the PGMFI system. By adding the IAC valve the ECM now had full control over the idle. The IAC valve is an electrically activated valve that controls the amount of air that bypasses the throttle blade. Now the ECM could increase the idle to offset the load from any event that occurred.

http://www.ef-honda.com/ben/ITRIMbentshit.jpg
 
There is coolant going into the iacv, but it has nothing to do with the control of how it operates. It is merely there to keep it from freezing up in cold conditions.
 
either me and you are not on the same page, or you have no clue.. im talking abou the lines comming off of the IACV.. and the two, the Big port up top, runs to the Booster, and the smaller port in the middle/lower region, can run to the FPR or the Cruis control..

Either way, im not seeing where those two black hoses are connected to Vaccum..
 
There is coolant going into the iacv, but it has nothing to do with the control of how it operates. It is merely there to keep it from freezing up in cold conditions.


dude, thats what ive been saying the entire time.. and you have been sitting here telling me those were not coolant lines, they were vaccum lines...
 
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