Skyline Owners Forum banner

1 - 14 of 14 Posts

·
Ut oh
Joined
·
3,796 Posts
Discussion Starter #1
when you remove the connector to the aac valve whilst the engines warm and idling should the rpm drop or stay constant?
 

·
Registered
Joined
·
34 Posts
would stay constant until the IAC needs to adjust the idle speed for any reason. At which point the engine may do strange things.

BTW - if yuo do this when the engine is running, you risk damaging the ECU
 

·
Registered
Joined
·
34 Posts
The AAC valve controls the idle speed. When the throttle is closed, the butterfly valve in the plenum closes completely. The air that keeps the engine running at idle all passes through the AAC valve. When the idle speed needs to be increased, the AAC valve opens a little more.

Hope this helps
 

·
Ut oh
Joined
·
3,796 Posts
Discussion Starter #5
the problem i was having is that i'd set the idle on the ecu via the turn screw but hadn't set the aac valve screw to the same.

Giving me an unsteady/lumpy idle...sorted it now though..:D
 

·
Ut oh
Joined
·
3,796 Posts
Discussion Starter #7
firstly i'm not 100% on this but its what i did.

locate the turn screw on the forward facing side of the ecu (the one you turn from left to right to put ecu into diagnostic mode)
you turn it anti clockwise to increase idle rpm and visa versa.

but you must keep over 40 degrees from the diagnostic postion.
find the idle rpm you want then pop the hood and locate the aac valve.

whilst idling on a warm engine disconnect the aac valve connector and idle should stay.

if it doesn't turn the adjust screw at the aac valve until it stays constant..same again anti to increase.

Sound right to everyone?
 

·
Registered
Joined
·
2,433 Posts
Cool...

But where's the aac valve when its at home? Gradually learning my way around the engine bay but there are just more gadgets in there than I ever saw on a lump of Iron before. (used to big block V8's - Tune it with a screwdriver and a stethoscope!)
 

·
Registered
Joined
·
34 Posts
Re: Cool...

Jock Alert said:
But where's the aac valve when its at home? Gradually learning my way around the engine bay but there are just more gadgets in there than I ever saw on a lump of Iron before. (used to big block V8's - Tune it with a screwdriver and a stethoscope!)
Ahh the goo old days - no ECU to interfere with the tuning! :D

here,

http://81.96.241.154/imgs/rb20idle.gif
 

·
Registered
Joined
·
4 Posts
Aac Valve

Hey I just recieved my motor I am here in the states, it dosn't have an AAC valve on it :bs2: , anyone know if it will interchange with any vehicles here. thanks for your time
PVT York

240sx
rb20det
t3/t4oe
reprogrammed ecu
550cc injectors
z32 mafs
3'' exhaust turbo back
fmic
walbaro 255 fuel pump
and some fuzzy dice
 

·
Registered
Joined
·
4 Posts
any advice

gtst lad said:
Dunno, sorry but an rb20det one shouldn't be to hard to locate from a jap dismantler.
anyone got any websites/phone numbers it would be very much appreciated, thanks for your time. by the way is fosters really aulstrialian for beer?
 

·
Registered
Joined
·
3 Posts
whoa whoa... im having cold idle problems.. i replaced my ecu with a chipped one .. i had no idea that screw has anything to do with idle... could this be my problem??
 
1 - 14 of 14 Posts
Top