Jump to content
SAU Community

Q For Tuners - Possible To Tune Without Iac Valve?

dori34

By dori34,
in Engines & Forced Induction

 Share

Recommended Posts

dori34 Grand Master

dori34

Posted
Posted

Hi gang, i just had a custom plenum nade for my 34 neo and ariel left the iac valve off as he advised me to check with my tuner first to see how he would prefer it mounted etc. as its off already and no plates have been welded, i was wondering if its possible to tune and allow the car to run/idle normally with it removed? If not, what will be a side effect of not running one?

i've read that the 34 setups are diff to 33 and most neo boys used 33 iac and tb. if i'm unable to tune it without the iac then whats needed to fit and get the 33 iac working. do the plugs fit or they need to be rewired ? does it matter if its from s1 or s2?

any help much appreciated :D cheers

Rolls Grand Master

Rolls

Posted
Posted

If you remove it how will the car idle? The throttle body is closed so there will be no source of air!

Definitely need an idle air control valve. Whether you can use a different one depends on how they are wired up, I imagine they are just a duty cycled solenoid much like an injector, so as long as the tuning software allows adjustment of the gain factor for the valve you should be able to really use anything.

Feel free to correct me if I am wrong though.

DVS JEZ Grand Master

DVS JEZ

Posted
Posted

it is best to have it or you can put an adjuster screw onto the throttle body to hold the throttle open slightly, this is a bodgy way as there is no adjustment for idle up during air con, lights on etc

put it in an easily accessible place that looks neat/ hidden. you will need to be able to run the hose from it to the intercooler pipe just before the throttle body

dori34 Grand Master

dori34

Posted
  • Author
Posted

hey fellas, cheers for the response.

will be running a nistune so i guess it would be best to have it installed. i'll look into fitting a r33 iac instead and hopefully i can find some information somehwere. i have a/c still and would like to keep it.

STATUS Grand Master

STATUS

Posted
Posted
hey fellas, cheers for the response.

will be running a nistune so i guess it would be best to have it installed. i'll look into fitting a r33 iac instead and hopefully i can find some information somehwere. i have a/c still and would like to keep it.

nistune will freak,

but like guilt-toy said generally it is no issue, map sensor based ecu's dont really care either way, but iac equiped car will always behave nicer especially on the street..

if its nistune use the r34 iac setup remote mounted.

dori34 Grand Master

dori34

Posted
  • Author
Posted

Hey trent, cheers for the info. can you enlighten me more on remotely mounting it.. does this mean i have to block the rear of the valve with a plate and tap a feed to the top of the valve instead? ariel mentioned something about this and said to consult with my tuner but i'm finding it so hard to get in contact with unigroup to get some answers..

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)
it is best to have it or you can put an adjuster screw onto the throttle body to hold the throttle open slightly, this is a bodgy way as there is no adjustment for idle up during air con, lights on etc

put it in an easily accessible place that looks neat/ hidden. you will need to be able to run the hose from it to the intercooler pipe just before the throttle body

RB25 throttle bodies have the adjustment screw allready there.

Just to quickly clarify, AAC (Auxiliary Air Control) is the hose that goes into the intercooler pipe to feed extra air into the engine when the throttle is shut and IAC (Idle Air Control) is the hose from the heater that feeds warm air into the engine when warming up, correct?

Question, how is it that a lot of cars from factory run fine without AAC (Such as a JZA80 Supra). Is it because they are map sensored so it makes it easier? I have tried pissing my AAC off back in the day but the Microtech simply hated it even though it is MAP sensored. So what's the go?

Edited by PM-R33
STATUS Grand Master

STATUS

Posted
Posted
RB25 throttle bodies have the adjustment screw allready there.

Just to quickly clarify, AAC (Auxiliary Air Control) is the hose that goes into the intercooler pipe to feed extra air into the engine when the throttle is shut and IAC (Idle Air Control) is the hose from the heater that feeds warm air into the engine when warming up, correct?

Question, how is it that a lot of cars from factory run fine without AAC (Such as a JZA80 Supra). Is it because they are map sensored so it makes it easier? I have tried pissing my AAC off back in the day but the Microtech simply hated it even though it is MAP sensored. So what's the go?

yeah map sensors dont actually get effected by minor airflow pulses etc so generally dont try compensate... hence rock solid idle.

You can even drill a small hole in the butterfly to help stabilise the idle.

but like previously mentioned its not all that nice for everyday streeters that need pwr steer, a/c etc load compensation.

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

Only reason I wanted to piss it off back in the day was due to not wanting to run the extra hose when going to the Plazmaman plenum. Now it doesn't really worry me since it is allready set up. It was mainly a "neater" option to not run one at the time :happy:

Edited by PM-R33
STATUS Grand Master

STATUS

Posted
Posted
will just end up getting the plenum modded to fit the IAC, would make life alot easier :D

why is the iac mount missing? is it an old version?

the ones on the website are like the one i had in the shop, had a bolt on position for the stock IAC.

THROTTLE%20BODY%208.jpg

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • soviet_merlin
      WGNC34 - floor mats

      By soviet_merlin · Posted

      I'd be very surprised if you can buy new OEM mats. But if you can, I want some too!  Do you have links to the variations you found? Also, where are you located? I found that Nengun is happy to list items to purchase but when you do buy them you'll get an email that it's actually discontinued. As far as I know the variations in floor mats are different colour schemes as well as automatic and manual having a slightly different shape. The automatic ones fit into a manual car without issues, but I think you'd have trouble fitting the other way around. I have photos that show the shape difference if you care. FWIW I bought sets of used floor mats in decent condition at yahoo auctions.
    • Marek
      WGNC34 - floor mats

      By Marek · Posted

      Hi 🙋‍♂️. Just bought my Unicorn but the interior need some minor work so it would match my expectations ;). I noticed it is hard to get used oem floor mats in good condition so i started to dig if there's any chance to buy set of new ones. I found two websites - nengun and amayama and it looks like one can still buy factory new floor mats in Japan, but thers a small issue. Some mats (i assume genuine, oem ones) are marked as G4900 and these are "discontinued". The ones you can buy are marked as G4911 but i have no idea if these are also oem, made by other producer or some lower quality replacements that looks entirely different. Can anyone help? 😃  P.s. there is also some strange indication - 0V005, 0V015 and 0V505. Any idea what does it mean? Would appreciate any help with this 🙏
    • Marek
      Hi everyone.

      By Marek · Posted

      Hi, Marek here 🙋‍♂️. I finally fulfilled my longtime dream - recently bought Stagea and now waiting for it to arrive in Poland. There's only few of these in my country, and one of the owners  recommended mi this forum as a source of all the info i'd need since now i own one  so here i am.  
    • The Bogan
      NC MX5

      By The Bogan · Posted

      Version 1 aluminium airbox is.......not acceptable No pics as I "didn't like the look.....alot" Even after all my "CAD", and measurements, the leg near the fusebox just didn't sit right as it ended up about 10mm long and made the angle of the dangle look wrong, the height was a little short as well, meh, I wasn't that confident that Version 1 was going to be an instant winner I might give Version 2 another go, there's plenty of aluminium at work, but, after having in on and off a few times, and laying in the old OEM airbox without the new pod filter and MAF, there may be an option to modify the OEM air box and still use the Autoexe front cover and filter.... maybe This >  Needs to fit in here, but using the panel, and not the pod, the MAF will need to fit in the airbox though> I'm thinking as the old OEM box and Autoexe cover that is sitting in the shed is just sitting around doing nothing, and they are relatively abundant and cheap to replace if I mess it up and need another, it may well fit with some modifications to how the Autoexe brackets mounts to the rad support, and some dremiling to move it get in there, should give me some more room for activities, as I don't want to move the MAF and affect the tune Sealing the hole it requires to stick it in the air box is simple, a tight fit and some pinch weld will seal it up tight  I am calling this a later problem though
    • Dose Pipe Sutututu
      Ethanol Content Sensor - Always at 11%?

      By Dose Pipe Sutututu · Posted

      and it ends up being already priced in as though you're just on 91RON without any ethanol. Car will lose a bit of economy as the short and long term fuel trims bring down the AFR back to stoich or whatever it is for cruise/idle for the engine.  
×
×
  • Create New...