Well, I found out the reason for my horrible idle from the nissan dealer... They told me that the AAC Valve (Auxilliary Air Control Valve) needs to be replaced, and my throttle body has carbon deposits clogging it up. The guy also insists that i replace the alternator but i refuse to spend $450 for a new alternator when I have an alternator already on the car that is under warranty for a whole year.

My question to u guys is if anybody knows where i can find this valve b/c the dealer wants $220 for it, and im trying to see if i can find it somewhere else cheaper. I ran a search thru google for it, but most of the results were for the 300 ZX TT and the SR20DET... One of the guys from in the faq's has a writeup on how to clean the TB so thats no problem, and as i stated before im not changing the alternator until i know its a problem, and even then ill just exchange it with the warranty... so any information on where i can find the AAC valve would be greatly appreciated, thanks...

 

Sometimes it stops working because it gets crudded up with carbon. Unless they told you that the motor on it was bad, I'd try taking it apart and cleaning it first, just like your TB. See if that helps. If not, you can try getting one from one of the Nissan parts sites on the net. May not save you too much money, tho.

 

try cleaning it.. if that doesn't work then buy another one..any yards around where u live?

 

cleaning it should do the trick. dealership just wants to get you in the *** with parts costs.

 

Thanks guys... Ill try cleaning it, along with the throttle body and let u know how that goes, if it works great, but if not i guess ill have to get another one... But id still much rather pay $220 dollars and fix it myself as opposed to giving the dealership $1000...

And yeah, there are quite a few junkyards around the way, I guess i could see how much they're charging...

 

Hi,

What were the symptoms for your "horrible idle"

 

When cold, the car would fluctuate its idle from 250-500... It shake pretty horribly and the battery and e-brake light would remain on (though im not sure if they're related to the aac valve problem). After you drive the car for some time (maybe a half hour or so) it goes away and the car will operate just fine (but the two lights still stay on).

 

well unless its a computer error brake + charging light means your alternator isnt really working. and From what i gather when the alternator/battery arent working properly, the valve does not open properly. If your alternator really is at fault and its not a false alarm, dont depend on your car to run for ya much longer. i think i got a week out of mine after my lights came on.

 

Magnifico is right, your alternator is definitely on it's last legs. Replaced mine last year, same lights on. Also could be right about the effects of that on the AAC valve, too. Makes sense. I still say remove it and clean it out if you've never done it. It needs it. But mainly, get that alternator replaced, and NOT at the dealer.

 

well it wont cost me anything to get the alternator replaced so, i guess that wouldnt hurt, but im still gonna clean the valve and the throttle body and see if that helps...

But about the lights they have been on since april... and im able to use everything, including a/c at full blast whenever i drive without consequence... but ill still get it changed though, since its under warranty...

Ill try and replace the alternator after i clean the valves, and if neither of those works then i guess ill have to just buy a new valve, but im determined this problem will be solved...

 

Yeah, maybe have the store bench test it at least, so you can rule that out. If you've had the lights on since April, that seems like it may be something in the circuit. When mine started doing that, the alternator was done in a matter of a few days.

 

most yards wont sell the valve alone it stays w the motor. i thought mine was bad but it was other problems .you can test that thing. from what i understand you hook up power to the diff terminals and watch it move in +out its like a r.c. car motor (i guess it controls air flow when cold and works w\the i.a.c. valve?(idle air control)(get new gaskets ) these must replace old stlye chokes (its like a bypass of the throttle plate since that is closed if your foots off the pedal ...you could clean the throttle plate since theres a sm. gap around it (airflow)that clogs )these =idle problems...

 

Well... i didnt replace the aac valve... but i cleaned the throttle body and put in Cold Air Intake.... and well... The rough idle is gone. It idles really high now though (about 1500 rpm... then it gradually comes down to about 1k) but i can adjust that so that it idles at the proper speed. I dont know if this completely solved the problem or not, but it is a temporary fix. The battery and brake lights are both still on so im gonna take u guys' advice and have the alternator tested and replace it if necessary, but i think im almost done... thanks guys

BTW, i had no idea how good cai sounds... now on to the exhaust

 

Can anyone tell me how to properly adjust the AAV valve? I do what hayes tells me to by turning the ECU all the way clockwise. Turing the aac in our out till the idle speed is at 750rpm. Then turn the ecu all the back to normal.

But still when start the car in the morning it REAL rough for 5 minutes. Also it's effecting my gas horribly. Am i missing something?

 

normally poor idle is due to clogged egr valve NOT iaac.