Can anyone give me some info on pulling / cleaning the IAC?

Nissan 300ZX technical discussion forum: Maintenance, performance, installations, modifications, how-to's and troubleshooting.
data_tho
Posts: 10
Joined: Sun Mar 28, 2021 4:40 pm
Car: 1997 Infiniti J30

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I have a 97 J30 which I believe is basically the same mill as you guys. Please correct me if wrong. There's not much support on the J30 forum so I thought I'd ask with you guys.

I had an intermittent crank/no-start and rough idle. I gave her some CRC intake and turbo cleaner which in combination with a fuel filter seems to have mostly solved the problem. But, being neurotic as I am, I'd like to give the IAC a good scrubbing since the idle still feels ever so slightly wonky.

Which brings me to my conundrum. I have no idea where the hell the thing is located. Description in the FSM isn't great and the only thread I found is 15 years old with the pictures removed. Any chance one of y'all could do me a solid and give me some info on pulling this sucker out? Many beers would be owed if you're ever in the Denver area.


scottgas
Posts: 176
Joined: Sat Aug 10, 2019 11:20 am
Car: 1996 Nissan 300ZX N/A steel roof

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I posted in another thread about my son's '96 NA with idle issues. Z1 mentioned idle air control valve. I could use some help also

itsa300zx
Posts: 1243
Joined: Sun May 31, 2009 9:39 am
Car: 1990 300zx NA W/TT swap
2011 Nissan Rouge S
2008 Highlander SR5
Location: up North

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Here is a pic of the idle control on the Z32: Rear driver side of the plenum.
Image

To remove, disconnect the rubber hoses to the IACV, three pain in the a$$ connectors (Air reg, ACC, FICD), undo the four 10mm bolts using 1/4" drive. Note there is a gasket in between. Removing the balance tube will give more room too. Stuff rags btw the firewall below the idle bolts will save you head aches when you drop stuff.

Apply 12 v to the AAC and you should hear an audible click.

Functions:
Air reg is to slowly close as the car warms up with a copper bi metal valve. If this fails, high idle, happens rarely

FICD opens a valve to allow air in when accessories are turn on to increase idle slightly. If this is stuck open, high idle, happens rarely

AAC is controlled by the ECU to maintain the idle value as set in the ECU ROM, it constantly clicks on/off duty cycle to set idle. If this fails, you will be unable to adjust the idle with the adjustment screw. Note that OEM ROM chip is set to approx 650-750 RPM, some aftermarket ROM chips are set as high as 900 RPM.

data_tho
Posts: 10
Joined: Sun Mar 28, 2021 4:40 pm
Car: 1997 Infiniti J30

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Fantastic! Thank you!


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