R32 Gtr High Idle

[ADM]

In fact with a bit of squeezing with long nose pliers its possible to shut of all possible leaks from the other air chamber feeds. On the front side (does that make sense) you have two feeds to the blow off valves and the carbon canister. On the rear side there is a single vacuum line that feeds the brake booster.

In my case blocking all these off made no difference to the idle speed. So my problem is not an air bypass system issue. However, I only replaced the two throttle body gaskets but not the intake manifold gasket as that would have involved removing the associated water cooling components as well. That’s the only other place that I could imagine there may be an air bypass style leak occurring.

I have an aftermarket fuel regulator on the car which I no nothing about. In fact I’m not sure what impact that could have on idle speed. Does any one know?

Other than that I might flick the air flow meters for a spare set just to see if that makes a difference ( although the consult shows it shouldn’t

[ookami]

so does this only affect R32 GTR? My R33 GTR also idles about 1100 RPM. It has only done this since getting it home and servicing it. It didn't originally do i when i first picked the car up - it sat at 900 then. It has a common issue with RB26s.

[atessa]

according to the underbonnet destructions, its supposed to idle at 650rpm. i've yet to see one that does. anyone? bueller? bueller?

mine runs at 1000rpm, but as i only idle at traffic lights, and everything else works - why worry? i aint gonna spend $1000 or more to fix a fast idle.

and yes, all gaskets are sweet, no air leaks (i replaced every external gasket once she landed on our shores) - although i'd be reluctant to pour water on a warm manifold -max 5 mins after startup for that trick.

[ADM]

The R32 GTR’s are supposed to idle at 950rpm. If the AAC is working correctly this will be the lowest the factory EPROM will allow it to idle. The work shop manual states that to set idle correctly, the AAC solenoid should be unplugged (or disabled via consult) and the idle speed should be set via the AAC idle adjustment screw to 900rpm. I guess this ensures the AAC solenoid regulates idle at the EPROM determined 950rpm. Of course if there is an issue such as a vacuum leak and the idle is artificially held above 950rpm then the ECU has no control (via the AAC) to regulate the idle. . If you have a consult program you can observe the AAC percentage vary to hold the idle at 950 rpm. Of course this only occurs at idle and only if the TPS idle switch point activates and provides the idle flag to the ECU. Again the consult will show the idle flag activate, followed by the AAC valve working to hold 950 rpm.

Edited June 30, 2006 by ADM

[cowie165]

Thanks for all the info ADM

What Consult software are you using? The freeware I'm using at the moment cannot conduct active tests. Is there any freeware that does?

[ADM]

Hi cowie165

I use NissanDataScan v1.5 which I purchased for $30, not sure about the free/demoware options. Although for only $30 you might aswell purchase the real thing.

http://home.curl.aunz.net/tpkolo/DataScan.htm

http://www.plmsdevelopments.com/consult_if.shtml

[ido10s]

Hey Guys,

i'm looking at replacing my aac in a few weeks so ill let you guys know how it goes.

[Fei Jai]

hey guys, i have a R34 GTT, it was sitting on 900 rpms, now after i changed the spark plugs to platinum, its idleing at 1100rpm, may sound stupid but maybe its the spark plugs or coil packs? im new to the car scene so please dont blast.

[andy95'R33GTR]

same problem R33GTR, 1,000 rpm cold, warm 1,200rpm

[djr81]

I had a hunt at idle in my R32 GT-R. The highly technical solution was to adjust the screw on the front of the AAC valve, ie turn it clockwise to lower the idle speed, turn it anti clockwise to raise it. The hunt went away & it now idles at the setting the ECU tells it to. Which is about 1100rpm for a power FC.

Basically the valve does two things: Allows more air in for a cold idle. Controls the air (hence the idle speed when the engine is warm. It is buried under the inlet manifold next to cylinder 4 or thereabouts.

If the motor is hunting it is usually that it is getting too much air for the desired idle speed as programmed into the ECU.

Edited November 20, 2009 by djr81

[andy95'R33GTR]

i will try to block the air regulator supply and check if the idle drops

[Brandon]

Cant you just adjust the idling? Thats what I saw a mechanic did to mine (adjust it down to 950) but when I brought it to the tuner, he put it back up to 1100. Dont know why. I didnt have any problem with the car when I was at 950 too.

[andy95'R33GTR]

full adjusted already... the AAC valve

[andy95'R33GTR]

any suggestions guys?

[GTR-Ben]

Check resistances etc for the AAC and Bypass valves and make sure they are actually working correctly.

Does anyone know if the Air Bypass Valves are the same across models or do they have different ranges??

[andy95'R33GTR]

hmm....i alrady check my AAC is working ok, already closed the vacuums of the AAC and the air regulator, so its not there, i am thinking it could be the timing? because i remember before i removed my CAS, after installing i didn't use a timing light, and also my injector 6 is leaking, could be the cause?

[LotusGTR]

The coating on the throttle blades is worn. So says my tuner. I have the same problem. STD ECU and PFC. The latter allowed some adjustment

[andy95'R33GTR]

how to check if i have worn throttle blades???

[LotusGTR]

You take them out, recoat with Teflon (I think), put them back in and hope that was the problem. Lots of $$ of fiddling for no sure result. Mugs game owning GTRs.

[andy95'R33GTR]

hmmmm ok thanx =) can this be detected by consult???