Diy Aac Valve Cleaning & Idle Reset.

[geraus]

So this cleaning wouldnt effect the maps on the power fc?

[imperio]

tried this diy this arvo but cant seems to get the hoses off no matter how hard i pull... am i doing it the right way by unclipping the hose clips first then pull.

[boiracer]

had my car for a week now, it stalled twice on the way home (350km's), only at idle in traffic, did this today fixed it good.

nice idle now, but i turned it up a little to 700, rather than the factory 650.

yes the hoses are on there pretty hard, dont be scared, all the pipes they push onto are metal and pretty strong, get a large screw driver behind the edge to help push and give it a twist to break the seal a little, but dont jam a screw driver under the hose.

[imperio]

managed to get it cleaned but had a hard time gettting the screw off from the aac.. there is a black rubber ring which i broke it when taking the screw out.. car doesnt have anymore stalling at idle but everytime when i clutched in my revs seems to stop at 1000rpm crusing then drop to 800 when car reaches complete stationary..

[boiracer]

hmmm, mines back and with avengeance.

done about 3500km's since last post. ive cleaned the AFM, wrapped coil packs, gapped plugs, checked for air leaks, reset the computer but with no change.

seems like it only does it sometimes, at first it was only after hrs of driving and everything under the bonnet was warm, but yesterday happened just after leaving my folks place early in the morning.

i think maybe the AAC only works somtimes? maybe its a bit faulty or on the way out so it only does its job occasionally?

makes it real hard to sit in traffic sometimes, managed to control the stall but requires some fancy foot work...which id rather not do in traffic

[chiksluvit]

awesome guide

I dont have any idle issues but did it anyway.

worst part was dropping the gasket and couldn't find where it was

found out 30 mins later that it was hanging on the steering rack

[BASHO]

Has anyone done this to an R34 N/A (RB25 NEO)? I've had a look at mine and it seems quite different to the R33 in the pics.

I have no issues with my car at the moment.

I'm just curious - because I wouldn't mind cleaning it, for the sake of keeping it maintained and I imagine it would also help with idling economy too.

X 2 , I have a slighty fast and a tad eratic idling issue and I want to clean this out first as the throttle body will be the next likely culprit and that looks like a PITA to do.

My main concerns are the three water hoses with what looks like a bleed screw on the top that connect to the AAC housing as I'm not sure whether the entire plenum is water heated or just the aac housing or in fact WTF this hose Christmas tree is all about , the rest of it seems pretty straight forward .

Can anyone please help explain the hose thingos .??

I have noted that the carby cleaner is quite explicit about NOT allowing it to come in contact with any sensors, stepper motors and the like so it's obviously pretty toxic--it's a Nulon one, so I'll be dismounting the sensor and cleaning it with contact cleaner separately.

Edited July 29, 2009 by BASHO

[meet07]

I have a rb25det S1 in a 240 with q45 tb and freddy intake manifold. I messed with the tb screw a while back and just read that I wasnt suppose to mess with throttle body. Is it suppose to be closed?? Every time i mess with my idle I cant get it right. In order for me to crank the car I have to hit the gas pedal like a carb. When I disconnect the tb plug, adjust the idle and then plug the tb back up the car drop idle. can I adjust the idle with the car warmed up?? I cleaned out the aav like 6 months ago. How often does it need to be done??

[Wacky Dee]

Ok this may sounds strange ..but I decided to give this DIY a go myself on a 1998 R34 GT-T with about 65k on the odo as I have some slight idle hunting issues when clutching in at the lights etc

So I removed the 4 bolts (slightly different to R33) and loosened the hoses a bit ..but the hoses were really stuck on and so I though I'd just take a look inside the AAC housing to check its condition before I remove all the hoses etc and whaddya know ...

THE INSIDE LOOKS BRAND NEW. I am serious, there's not a TRACE of carbon buildup. All the walls look new and shiny and even the spring is shiny and looks brand new. No trace of dirt/carbon buildup ANYWHERE whatsoever.

Hm, what gives? Has anyone else cleaned the AAC valve/housing on their R34 GTT and found the same ?

[08r3308]

Ok this may sounds strange ..but I decided to give this DIY a go myself on a 1998 R34 GT-T with about 65k on the odo as I have some slight idle hunting issues when clutching in at the lights etc

So I removed the 4 bolts (slightly different to R33) and loosened the hoses a bit ..but the hoses were really stuck on and so I though I'd just take a look inside the AAC housing to check its condition before I remove all the hoses etc and whaddya know ...

THE INSIDE LOOKS BRAND NEW. I am serious, there's not a TRACE of carbon buildup. All the walls look new and shiny and even the spring is shiny and looks brand new. No trace of dirt/carbon buildup ANYWHERE whatsoever.

Hm, what gives? Has anyone else cleaned the AAC valve/housing on their R34 GTT and found the same ?

hey i found that sometimes even if it looks clean give it a spray and some buildup will come out, worth a try .

how many km on yours ?

[meet07]

what happens if you remove the aac valve and adjust the idle with the tb.. Freind of mine with a ca18 removed his b/c his custom intake manifold was fitted for one? cause me personally, I hate the aac valve

[Wacky Dee]

hey i found that sometimes even if it looks clean give it a spray and some buildup will come out, worth a try .

how many km on yours ?

65000 or thereabouts .. you don't get it, there is NO dirt in there. The pain of ripping those 4 hoses out to 'clean' something that is practically new inside is not worth it. The brass looks like brass and is shiny. The walls are still alloi colour and shiny/brand new (much cleaner and shinier than on the outside). No carbon deposits what-so-ever.

[08r3308]

i found with mine was pretty clean but once you spray inside little holes and move the spring that's where i found most build up was.

how many rpm on idle?

did you check your afm ?

there was a post on someone fixing up afms by soldering connection, this might be the case also.

mine had a bit of issue with idle and i found by doing these steps it fixed now

[Wacky Dee]

I just couldnt justify screwing around with all the hoses (4 of them on the GTT) as they seemed very hard to get off after seeing how clean the inside was ..literally brand new or atleast looked that way. is your a GTT or v35?

my AFM wiring harness seems solid .. no loose wires. I'm gonna get a nissan consult cable (ecutalk.com) and check all the sensors using consult programs to make sure AFM voltage is ok etc.

RPM sits at 850-900 on idle ..no hunting, but when clutching in at lights, moving steering wheel when stationary it does hunt a bit (3-5 seconds)

[BASHO]

OK, I cleaned the AAC valve on my 98 R34GT-t (79000ks) not (after taking it off) that it appeared to need cleaning, reasembled the thing, took it for a drive to get everything warmed up, unpluged the sensor, set the idle to 650rpm gave the engine a couple of mild revs waited for it to settle, pluged the sensor back in WAP back up to 800rpm WTF is it with this fricken thing.

I've reset the idle with the sensor pluged in but cant get better than 750rpm with the adjuster near closed.

I'm obviously missing something.

Any ideas anyone ?

Edited August 6, 2009 by BASHO

[meet07]

OK, I cleaned the AAC valve on my 98 R34GT-t (79000ks) not (after taking it off) that it appeared to need cleaning, reasembled the thing, took it for a drive to get everything warmed up, unpluged the sensor, set the idle to 650rpm gave the engine a couple of mild revs waited for it to settle, pluged the sensor back in WAP back up to 800rpm WTF is it with this fricken thing.

I've reset the idle with the sensor pluged in but cant get better than 750rpm with the adjuster near closed.

I'm obviously missing something.

Any ideas anyone ?

Im having a similar problem but I messed with my q45 throttle body. And now I cant get my idle right or my tps. Thats what I get for messing with it. It was fine before. and this procedure isnt doing me any good......

[SiR_RB]

ok im gona giv this ago on my r33 tomorow....now im abit worried about the screw thing....if i undo the idle screw to clean it, how do i no how much to tighten it to adjust the revs properly?

im worried that i might stuff up the revs and wont be able to correct it again

from wot i understood, u can adjust the revs of the car from that screw while its running??

any info would be a great help !!

[RicsR33]

I just couldnt justify screwing around with all the hoses (4 of them on the GTT) as they seemed very hard to get off after seeing how clean the inside was ..literally brand new or atleast looked that way. is your a GTT or v35?

my AFM wiring harness seems solid .. no loose wires. I'm gonna get a nissan consult cable (ecutalk.com) and check all the sensors using consult programs to make sure AFM voltage is ok etc.

RPM sits at 850-900 on idle ..no hunting, but when clutching in at lights, moving steering wheel when stationary it does hunt a bit (3-5 seconds)

Like a few people said it may look clean but it still has build up.. if you really wanted to fix it you would be trying everything you read and not making assumptions on what it is.

[MSTRshenanigans]

Thanks for the guide OP.

Did it in 40mins including stopping to drink beers. The cotton buds came off super dirty...

[nissans52]

Just finished this... cleaned my R32 RB20DET, 95K on the clock real easy to get to 4 bolts at the back of the plenum lol my was full of carbon lol cleaned it all out got lucky too took the screw out cleaned it all up and put it back roughy were it was sitting b4 and now NO more stalling at lights and the idle sits dead on 750 now instead of jumping around 500 to 850 and only took about half an hour lol would also advise to cleaning the plenum were the aac valve bolts onto that was full of carbon too just used the cotten buds with carby cleaner on that but yeah great write up

Edited October 7, 2009 by nissans52