Aac Valve

[GTAHH]

G'day, I tried searching and couldn't really find what I need.

Basically today I took off the AAC valve on my RB20 and gave it a good clean with carby cleaner. I removed the whole thing (4 Hex bolts) and I un-screwed the two screws holding the solenoid looking thing on. I gave the whole thing a clean, and put it all back together and reconnected it, started it, and it idles very high, and when it's warmed up it can't sit on it's high idle (2000rpm), it continues surging from 1000-2000 when it gets warmer.

When its running I can disonnect the connector and it stills continues what it's doing without any change. So I guess I put it all together incorrectly? Can someone give me some pointers how to put it back together correctly? Maybe I have put the plunger the wrong way or something silly like that?

I have disconnected the battery for a day or so to reset the ECU, incase it isn't used to a clean valve or something like that

Cheers all

Edited November 2, 2005 by GTAHH

[GTAHH]

Post edited

[GTAHH]

Anyone? Any advice is good

[RellikZephyr]

i had the same problem and finally found it was actually my air regulator (slightly stuck open) mine was a 32 GTR so i dont know where your air regulator might be

but it could be worth checking that out

Good Luck

RellikZephyr

[The Dan]

The air regulator can effect the idle like this and is located behind the injector fuel rail about 3/4 of the way back towards the firewall. I would not advise cleaning this or if you do be very careful. There is a nut on it covered in locktight and is there to adjust the gate inside for how much air to alow past. You can successfully clean this item without too much drama but try not to play with the locktighted nut. If you do have to play with it, set it so the gate is fully open. Have you had your TPS or MAF meter checked?

Also give the entire intake system a good cleanout to ensure no gunk is present on the throttle body, MAF meter or any of the pipework.

Also check to make sure you don't have an air leak somewhere. You can use carbi clean to locate the source of any air leaks.

[predator]

when you replaced the ACC you didn't lose the little valve thing in there did you? probably not, but just thought I'd suggest

[GTAHH]

Cheers lads, I just find it abit strange that it only did it after I reconnected the AAC valve after I took it apart and cleaned it.

Ill give them a try so I don't have a 1000-2000rpm idle

Cheers

[GTAHH]

when you replaced the ACC you didn't lose the little valve thing in there did you? probably not, but just thought I'd suggest

<{POST_SNAPBACK}>

The little plunger thingo inside it? Noooo

Edited November 3, 2005 by GTAHH

[midnight]

Also check to make sure you don't have an air leak somewhere. You can use carbi clean to locate the source of any air leaks.

<{POST_SNAPBACK}>

how does carby cleaner find leaks? does it affect idle or something when you spray it on a vac leak?

Edited November 3, 2005 by midnight

[The Dan]

Yes, it effects idle when you spray it over a vacuum leak.

Just another quick question....you did reset the idle after cleaning the thing out didn't you because if you have the screw wound all the way out it will leak air past and cause it to hunt like that.

Try winding the screw in all the way - it should konk out when it's almost all the way in, then just wind out slowly until idle comes good.

[GTAHH]

Yeah champ just left it disconnected for over 24hrs to test if that might fix it. Will try and get into it tomorrow hopefully with good news. I will definatley try winding in the idle screw if it still continues before I try all the other steps.

Hopefully comes good

Cheers again

Edited November 3, 2005 by GTAHH

[GTAHH]

Yes, it effects idle when you spray it over a vacuum leak.

Just another quick question....you did reset the idle after cleaning the thing out didn't you because if you have the screw wound all the way out it will leak air past and cause it to hunt like that.

Try winding the screw in all the way - it should konk out when it's almost all the way in, then just wind out slowly until idle comes good.

<{POST_SNAPBACK}>

I've wound it all the way in and it seems to drop idle by around 300rev's, so its around 1500 and it doesn't seem to be doing the surging as much anymore it's just got a 1500+ rpm idle very strange. It still does the surging but not as often

I took off the hose going to the reg valve (while running), and the idle settles down to just above 1000, when I block the part of the T-piece going to the reg valve(where the hoses separate to go to the aac and the reg valve) the revs increase.

So i.e with the engine running and with the hose to the reg valve not connected and not blocked it runs a lower idle around 1000. If I block it, than it runs a higher idle.

So that means the reg valve is stuck open?

Edited November 4, 2005 by GTAHH

[GTAHH]

Oh and when I block the hose going to the AAC valve it runs like crap and stalls?

This normal?

Each time I take the AAC assembly off and re-assemble it, it does something different, sometimes idles higher, sometimes doesn't surge.

Cheers!

Edited November 4, 2005 by GTAHH

[gt-t_r34]

in my r32 gtst i took it off the other day to check the spring was still sitting straight because it did the funny idel jumping thing once and yerh was still ok but i fiddled with the idle adjuster screw + shaped faces out ways when the acc is on towards the drivers side so maybe if you take your aac of again check the spring and put it pack on start the car and adjust it from there to where you want the idle to sit remember it idle a little higher when cold so set it to about 1,000rpm maybe a little lower

cheers

Edited November 4, 2005 by gt-t_r34