Diy Aac Valve Cleaning & Idle Reset.

[benl1981]

You shouldnt need to play with the TPS right?

I dont want to change things as the car has been tuned. I do get the occassional hunt though..bit annoying

[markimak]

no guide to doin this on a R32 GTR idle control screw is under the plenum so im told. my GTR idles at 1000rpm warm.

[Endless604]

i just did it on my R32 (rb20det)

took about 30mins, had the ecu out too, but didn't have to touch it. I used combustion chamber cleaner instead, and set the idle to 900rpm warm...up from 600rpm (factory spec)

idle's much smoother, no more stalling issues with the hks ssqv, annoying stalls with the A/C on, or stuttering when clutching in and decellerating.... or rpms dropping when im driving with the headlights on and heater on at night. this is such a wicked faq. there is no excuse not to clean/inspect your AAC valve!

THANKS INSU

[GTR_Legend]

stopped the stalling on mine, but sometimes the revs will sit @ 1-1.5k for a few seconds the drop.

Could this be because the idle screw is not in enough?

[cooks44]

When I took mine off for the clean I took the idle adjust screw all the way out. Around it was a rubber sleeve. Now whenever I try to screw it back in the sleeve just rolls up the screw and I'm concerend that air may leak in through any gaps.

Anyone got any suggestions on how to get this rubber to seat on the screw inside the thread again??

What else do you do when you're playing with a screw and you can't get the rubber in?? Whack a bit of lube on it! Bit of Vase', you'll be fine.

I believe the rubber is only there to prevent the screw from adjusting with engine vibration and such.

[RT33]

this solved the fluctuation in the revs and stopped my car from stalling. it only take about 30 mins if you know what your doing. i didn't even have to adjust the idle after it was perfect.

even if you dont have rev or stalling problems i highly recomend you do this.

BIG THANKS to INSU for this diy

i don't hate my car anymore thanks to you!!!

[Guest tosboost2]

sorry guys, just a quick question does the aac valve have a gasket under it?

[heslo]

Yes, it does have a gasket

[prosman]

great tutorial, helped me immensely in cleaning my aac valve on my r32 gts-t. two things i have noticed though, on my car you had to disconnect the TPS rather than the brown plug on the AAC valve to adjust the AAC idle as you would on an r33. secondly, did anyone else find it ridiculously hard to screw in the idle screw while adjusting the AAC valve idle? i dunno why but i got it down to about 900rpm and its pretty much stopped moving.

anyways thanks again dude great writeup!

[Dose Pipe Sutututu]

great tutorial, helped me immensely in cleaning my aac valve on my r32 gts-t. two things i have noticed though, on my car you had to disconnect the TPS rather than the brown plug on the AAC valve to adjust the AAC idle as you would on an r33. secondly, did anyone else find it ridiculously hard to screw in the idle screw while adjusting the AAC valve idle? i dunno why but i got it down to about 900rpm and its pretty much stopped moving.

anyways thanks again dude great writeup!

If it was ridicuously hard to turn, probably the O-ring on the AAC Value screw is all dry and crumbling. Time to replace that O-ring.

When I took out my AAC value, I removed the screw, the Solenoid, the piston and spring inside and gave it a good clean with carby cleaner. Put it all back together using carby cleaner as a lubricant and replaced the old tired O-ring. Cost my $0.50 for the O-ring.

[benl1981]

If it was ridicuously hard to turn, probably the O-ring on the AAC Value screw is all dry and crumbling. Time to replace that O-ring.

When I took out my AAC value, I removed the screw, the Solenoid, the piston and spring inside and gave it a good clean with carby cleaner. Put it all back together using carby cleaner as a lubricant and replaced the old tired O-ring. Cost my $0.50 for the O-ring.

Did you ask for a receipt?

[benl1981]

Did you ask for a receipt?

I've just got to the stage where I have pulled it out ready for cleaning. Jeez it's fiddly!!

I'm looking in your pics as when I pulled the last hose off I think I knocked some bit of plastic or something down around and settled in the many cavities beside the engine. Can't see it, I hope I remember to jack the car after all this and see if I can see it from the bottom.

Wierd thing is I can't see any clips or other bits I am missing (compared with your photos)

I guess that's what I get for doing things at night

Hope it fixes the occassional hunting.

My car will be fine for a month or so - then a hot day or add the A/C and you'll get rev hunting for 5 minutes or so..

quite random..

[benl1981]

Ok - all done. Cleaned it up..but I got a hint of the hunting again today. maybe part of it is faulty?

Anybody else found this.

It will be ok for a few days then for a bout 30 seconds the idle will fall and rise...the injector duty cycle stays the same (I have PFC)..

Sounds very much like it is the AAV and that is why I cleaned it.

[Dose Pipe Sutututu]

The funny thing is that my idle is pretty much perfect, but adjusting the ECU's fine adjustment screw does nothing at all, winding left or right does not affect my idle.. weird.

Is it because I'm using a remapped ECU? with the rev limiter taken out?

[Mike_]

Very well written DIY, but my car is still idle hunting.

Will need to check all hoses for leaks etc.

Edited October 26, 2006 by Mike_

[god's rx]

I tryed this today and all was going well, i adjusted the idle with the brown bit unplugged (i have a 1989 R32 Skyline) and then plugged back in, revs were nice at 1000rpm then i turned her off, started her up and instantly the revs were up around 1600rpm. i then tryed again this time with the TPS disconnected and then re-connected and the best i can get is about 1500rpm (including adjustin the ECU idle).

Seems to backfire and burble on engine breaking a lot more but still feel smooth when driving

Could this be leaks or should i now try the IAC valve under the throttle body?

initial reason for cleaning the AAC valve was idle hunting and stalling which i still suspect to be a dodgey BOV but now i cant get the engine to idle how it used to (even if it was stalling).

Edited October 25, 2006 by god's rx

[GTS4-32]

I just cleaned mine out, alot easier than i thought...took about 45min for a beginner.

Yea i also had troubles putting the idle screw back in, but what i did was unscrew it out, then back in, back n forth pretty much until it found its way back in the hole pretty smoothly. Now my idle sits steadely on 900rpm wen warmed up. Great DIY Insu, solved my stalling issue.

[WogsRus]

My ECU adjustment screw does nothign aswell, not a thing. I have cleaned my ACC valve ect, but on the R33 if i disconnect the Tp it does not idle below 900rpm, eaven with the ACC screw all the way in. No go for me. I think my Cold start valve is stuffed or not closing.

I have tested for air leaks, but no good there either.

[kingy_06]

just performed on my 32 and went sweet, really helped all the problems! One thing though..when i was adjusting the idle screw on the side of the ecu, it didnt nothing at all and i think i may have gone past the 12 o'clock point! Is this ok, any side affects? It did nothing to my idle!

[insu]

just performed on my 32 and went sweet, really helped all the problems! One thing though..when i was adjusting the idle screw on the side of the ecu, it didnt nothing at all and i think i may have gone past the 12 o'clock point! Is this ok, any side affects? It did nothing to my idle!

The ecu is only meant to adjust the idle in 50rpm increments from memory, and should only be used if for some reason your car isn't idling as it should from the idle by-pass screw. Even through the whole range of the screw which is like 70deg or something, there isn't much adjustment there.

I wouldn't worry about it too much, cause i've never heard of anyone having to use the computer adjustment.

As for going pas 12 o'clock, if you do it puts the car in diagnostic mode from memory. Shouldn't be a problem if you turned back. If you turned it beyond 3-4 o'clock i think it is thou, you can f**k the little switch, so don't do that.