Eliminate / Delete IACV ??

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YBLEGAL

Regular Member w/ Cheese
I searched a lot with no success. Does anyone know how to eliminate the IACV and not throw a code?

I have a Hondata s200 (no option to eliminate), on an OBD1 B16.

Is there a resistor or something I can get or make to eliminate the error code it will create and make the ecu work properly? I'm good with electronics, but I don't necessarily want to reinvent the wheel if someone already knows what the ecu wants to expect and what to trick it with.

I want to completly remove it, and just put a block off plate there. A few times, I've ran it without the IACV and a code and it ran more raw. The rpms dropped off nice and crisp and fell flat at ~700rpm every time, never an issue, and a lot nicer than with the IACV. Even better throttle response. But of course I got a code.

Must be possible if you can get ITBs, I would imagine...
 
i'm running hondata dude. i have the rom editor software, and there's nothing for disabling it, just adjusting the duty cycle. maybe AEM EMS, but fuck that.

there's got to be a way. who knows what's best to tune ITBs with? anyone know the reason why the Toda ITBs work with hondata? i read most ITBs can't be tuned with hondata. these answers might be relavent.

help still :confused:
 
i'm running hondata dude. i have the rom editor software, and there's nothing for disabling it, just adjusting the duty cycle. maybe AEM EMS, but fuck that.

there's got to be a way. who knows what's best to tune ITBs with? anyone know the reason why the Toda ITBs work with hondata? i read most ITBs can't be tuned with hondata. these answers might be relavent.

help still :confused:

Hondata can be tuned for ITB's. Maybe your s300 cant. :) As far as deleting your iacv, I don't recommend it. DEFI can be tuned for ITB's but that isn't cheap. You may as well go with the AEM EMS, it is cheaper.
 
Hondata can be tuned for ITB's. Maybe your s300 cant. :) As far as deleting your iacv, I don't recommend it. DEFI can be tuned for ITB's but that isn't cheap. You may as well go with the AEM EMS, it is cheaper.

i'm not sure where your looking at prices. or where your reading my posts at. maybe it was ur typo, but I have an s200 as stated in my first post. As far as AEM EMS being cheaper than Hondata, nope, far from it. At $1,350.00 I say fuck that.

i'm looking here: AEM COMPUTER EMS Plug & Play Programmable Engine Management System @ Modacar

I spent ~650 for my hondata s200 & the rom editor software & moates burn1 & a chip/socket/etc. WAY cheaper than AEM EMS.

You may not recommend removing my IACV, but I do. lol. sorry for sounding like a dick, but i've seen example data logs of B16s purpose built for race and most didnt have an IACV. And like i said, it [edit: my motor] seemed to have better throttle response without it. Plus it idled better. So i want to try. Cant do any harm. I can just put it back to normal if it creates a problem.

but idk, i'm asking a kind of 'hard' question and so far i'm seeing answers like you didnt even read my question... maybe i'll just have to figure it out when my car's put back together and running again?

sigh.
 
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Alright I gave him a heads up.

I know. It's not. I just liked the behaviour of my motor when the iacv wasnt operating. I just gotta learn on my own i guess.

Atleast I can't really break anything, unless I'm a self-stated idiot. :)

Thanks tho
 
i'm not sure where your looking at prices. or where your reading my posts at. maybe it was ur typo, but I have an s200 as stated in my first post. As far as AEM EMS being cheaper than Hondata, nope, far from it. At $1,350.00 I say fuck that.

i'm looking here: AEM COMPUTER EMS Plug & Play Programmable Engine Management System @ Modacar

I spent ~650 for my hondata s200 & the rom editor software & moates burn1 & a chip/socket/etc. WAY cheaper than AEM EMS.

You may not recommend removing my IACV, but I do. lol. sorry for sounding like a dick, but i've seen example data logs of B16s purpose built for race and most didnt have an IACV. And like i said, it [edit: my motor] seemed to have better throttle response without it. Plus it idled better. So i want to try. Cant do any harm. I can just put it back to normal if it creates a problem.

but idk, i'm asking a kind of 'hard' question and so far i'm seeing answers like you didnt even read my question... maybe i'll just have to figure it out when my car's put back together and running again?

sigh.

I actually didn't see s200, I was merely using s300 as an example. And I said AEM EMS is cheaper than DEFI. DEFI is $1200 + $$ for the harness. I get AEM EMS for $1100 flat from my tuner IF I want it but I have never used it nor have had the need to. Street cars can run just fine with Crome or an s300 or equivalent.
 
Sure your not thinking of the FITV? I've already eliminated that.

And, I have no a/c anymore either. My understanding of the IACV revolves around maintaining 1 particular level of idle. Except when the coolant isn't up to temp yet; the FITV raises the idle outside of the IACV's duty cycle, but the ECU is smart enough to not fight it when the temp is low. I thought the IACV was more for when various loads mess up the idle level, such as a/c.

Not a race car, yes. But no a/c because I have a sunroof. Our summers rarely get to 100f. Just so I keep the heat for the winter. :p
 
Because the IACV is still being electonicly controlled when it's in that situation. The ECU doesnt know what amount of air is getting past the IACV anymore when debries are interfering. Thus the ECU keeps searching.

That's what I thought.

But what I don't know yet is if current controlling the IACV must be kept at a particular voltage to maintain the IACV's pluger position, or if voltage to the IACV causes it to move [period], like a motor in something like a drill.

So either (theoreticly):

3.2v may hold the IACV at 70%, and raising it to 3.8v would move and then hold the IACV at 80%

or

0v may hold the IACV at 70%, and raising it to 1v would move the IACV up, and AH, thinking as I type, I think I eliminated this possibility. Or would reverse polarity make the plunger move the opposite direction.

Oh boy.
 
Wow that was SOO informative. So it does hold the valve against spring tension with a pulse signal, awesome. And, it uses a longer pulse to hold the valve open when the temperatures are colder, correct as always Blanco. I think I know enough about it now to do what ever I want.

This is what I'm gonna do:
I'm deep into my wire tuck. The mechanic who swapped my motor used an OBD2 -> OBD1 conversion harness and it didn't match everything up of course. I've always had some really weird issues ever since the swap. Now that I'm rewiring everything, I've taken the opertunity to fix everything and integrate it correctly. For instance, hondata's data showed me that the Starter Signal Switch (STS) never came on. And when wiring, of course I discovered why. And I've installed a hondata intake manifold gasket and new throttle body gasket, so all the intake gaskets should be working properly now. So when it's all back together, I'll give the IACV another go. And I don't think I'll be able to eliminate it easily since it's so dynamic (the ECU expects the engine speed to change when it makes adjustments). PS, the FITV is already gone, regardless.

I'll post back if I ever do eliminate it, for the sake of information. ..I still may.

If anyone has direction with hondata, crome, or just an OEM ECU, please post it up. I couldn't find anything on it, especially here on Hondaswap.

but for now. that link owned me.

/thread
 
<strike>Yeah, I would completely expect an option to disable the CEL.

Unfortunatly Hondata doesn't have that option.

And since it's not that purpose built race car, I don't think I'll change just for the IACV.</strike>

-> I just figured now would be a good time to download a new copy of Rom Editor 4 for the Hondata s200, and it looks like they've released a new version! I installed the new version, and low and behold they've added a 'Disable IAC Error' checkbox in the Idle tab. If your a veteran of RomEditor's, this new version is more like the s300 Rom Editor now.

I guess i have to retract my previous statement. lol.

Graciously Hondata does have that option. :) yay.
 
But

looks like i'll have to shell out another $125 to upgrade from RomEditor3 to RomEditor4 with the 'custom serial to usb' data cable. w/e. just an FYI
 
Sorry that would be pointless, I like my data logging. And you can't do data logging with crome without buying the tuner from a dealer in conjunction with crome pro. That stuff is $354. It also seems that by upgrading to RomEditor4 it includes boost tables. So that saves me the $200 charge with the RE3.

But thank you for the offer. I know how to use bit torrent tho :)
 
All you need to do is disable the CEL for the IACV, that's it. I'm pretty sure Hondata has an option to disable CEL's...it's been over a year since I've been in Hondata, but I'm 99.999% positive it's there somewhere. You might try contacting someone at Hondata and asking them; their email is sales@hondata.com , and provide them with the following information when you email them:
  • Your name.
  • Your location (country, state and city).
  • Car model and year.
  • Engine type.
  • ECU number
  • Modifications (engine - not suspension!)
 
why remove it?? you could caps the nipples for the coolant lines and connect the lines together so coolant still flows, but not through the iacv.. i've heard that drops intake temperatures, especially w/ the Hondata intake gasket
 
Crome Pro has datalogging features, allows you to disable IACV, ITB support, etc.
 
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