Will no Idle at cold start up

JOE SHELLE

MEMBER
2001 NISSAN SENTRA
2.0L
4 CYL
2WD
AUTOMATIC
220,000 MILES

I have to accelerate for a few minutes and then it will idle. However it idles very low.
Would the "idle speed control-fi pot" have anything to do with this?
I noticed it seems to operate backwards. The plunger moves outward to the throttle body accelerator lever when I turn the engine off.
When the engine is running the plunger is retracted far away from the throttle body accelerator lever.
i'm not exactly sure what this "idle speed control-fi pot" is supposed to do when the engine is running, but i'm assuming is should control the idle speed under a load as the vacuum conditions change when the engine is under a load.
See part:16182n in the attached picture for reference.
any comments would be appreciated. Thanks in advance.

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4 Replies

SCGRANTURISMO

MECHANIC
4,897 POSTS

Hello,

This could be a problem with your vehicle's IACV-AAC Valve with is located under the throttle body of your vehicle. It is responsible for keeping your vehicle idling by letting air bypass the closed throttle plate at idle and is control by your vehicle's Power-train Control Module[PCM] or "computer". In the diagrams down below I have included the description of your vehicle idle speed system, and diagrams of where it is located. Here is a link describing how to change an idle air control motor below:

https://www.2carpros.com/articles/how-to-replace-an-idle-speed-control-motor-iac

Please go through these guides and get back to us with how everything turns out.

Thanks,
Alex
2CarPros

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Sunday, November 3rd, 2019 AT 1:07 AM

JOE SHELLE

MEMBER
2 POSTS

Have replaced the IACV several times.
When I check the IACV for movement it does not appear to move when turning the ignition on and off.
The connector was brittle and I replaced it, checked for correct voltages and they are present, but IACV still doesn't move.
Service Engine Light comes on and points to the IACV again.
Lifetime warranty and picking up another one today and will swap out and check for movement on plunger.
Hope I get a good working one this time.
Will let you know the results.
Thanks.

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Monday, November 4th, 2019 AT 9:46 AM

JOE SHELLE

MEMBER
2 POSTS

Done.
But what is the vacuum controlled component's function, I attached with my initial email?
It doesn't seem to be operating as I expected.
You didn't answer that from what I see.

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Monday, November 4th, 2019 AT 12:17 PM

SCGRANTURISMO

MECHANIC
4,897 POSTS

Hello again,

The part you are referring to is called the IACV-AAC valve. It is responsible for diverting air around the closed throttle plate so your vehicle can idle.

Thanks,
Alex
2CarPros

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Monday, November 4th, 2019 AT 3:46 PM