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I have a 1992 R32 GTR that has some idling issues. New motor and R34 Vspec II turbos with about 2,000 miles.

After it is warmed up sometimes it will idle upwards of 1,300 to 1,800 rpms sometimes it wont. Then sometimes it will idle at 1,300rpm and repeadily surge about every second steadily. The two MAF"s were just replaced and the catch can is empty. I did the research and found out that it might be the AAV.

Where is this AVV at?

If this issue continues after I clean the AAV, what else could it possibly be? I dont think a spark plug would cause this but who knows. It's a pain in the @$$ to find spark plugs here in Korea.

its an AAC valve... it sits under the plenum.... it controls the air going into the engine. when the throttle is closed......

give it a clean but idsay if it does it when it is warm its either ur tps or ur air regulator,.......

give it a clean any way...

try resetting the ecu after u clean it...... also

I have the powerFC. How do I reset it without losing the tune? Is it just like a normal ECU, unhook the battery for a few minutes?

Thank you for the local on the AVV btw.

Edited by Soju

Can't reset a PFC.

High idle on a GT-R is commonly a result of cleaning the throttle bodies around the butterflies (which you shouldn't do).

According to the workshop manual, the idle air adjustment is on the AAC valve.

Can't reset a PFC.

High idle on a GT-R is commonly a result of cleaning the throttle bodies around the butterflies (which you shouldn't do).

According to the workshop manual, the idle air adjustment is on the AAC valve.

I didnt clean the throttle bodies since I have owned the car. The previous owner didnt either that I know of.

Tomorrow morning I am going to clean the AAV and change the plugs if I can find a set locally. I will look for the idle air adjustment too. Hopefully this will fix it.

Oh another thing that started two days ago which I have to check also is the exhaust temp gauge is going hay wire, as in slamming the needle back and forth like a baby playing with a rattle.

I appreciate all the input honestly guys, the nearest shop I would trust to work on the car is about a 3 hour drive. So doing alot of learning. I am used to NA motors, had an EVO 9 for a few months though. It was brand new so nothing to fix, LOL.

nope. there is a how too... its 4 bolts.... pretty easy.. try running some injector cleaner through or get ur injectors cleaned... and replace the o-rings. it wont be ur throttle bodies.... its most likely a vacume leak form somwhere......try clamping off ur hoses to find if one has a pin hole in it.......

it could also be ur one way valve (pcv valve) conects to ur rocker cover breathers via hose.... clamp the hose off when its revving high to see if that fixeds it......

nope. there is a how too... its 4 bolts.... pretty easy.. try running some injector cleaner through or get ur injectors cleaned... and replace the o-rings. it wont be ur throttle bodies.... its most likely a vacume leak form somwhere......try clamping off ur hoses to find if one has a pin hole in it.......

it could also be ur one way valve (pcv valve) conects to ur rocker cover breathers via hose.... clamp the hose off when its revving high to see if that fixeds it......

So I cleaned the AAV, that wasnt the problem. According to my Power FC, the O2 voltage is 3.94 and the car is running rich. Could that be it? The surging problem is fixed, my 4 year old daughter messed with the idle settings when I wasnt looking and the wife didnt know that the hand held was vital to the car.

they run pretty rich on idle anyway with a standard ish tune....thats just a gtr thing.... yeah id prob look at the idle settings you can try and replace the o2 sensor but it will always run rich...

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