Idle speed increasing

Hello, I am Danny.

I would service the throttle body. I have attached two pictures and a tutorial for you to view. Hope this helps and thanks for using 2CarPros.


https://www.2carpros.com/articles/throttle-actuator-service

and

https://www.2carpros.com/articles/engine-idles-too-high


Please run down these guides and report back.

Only this throttle body if I turn the AC comes to low 400 rpm if turn off the AC comes to normal 800 to 900.

Hello again.

Is this what the throttle body on your car looks like? What size is the engine?
Danny-

1.6 Chevrolet Optra 2004.

Hello again.

I have attached a picture of what the Idle Air Control Valve looks like. Do you see this located on your throttle body? I have also attached a relearn procedure. Hope this helps and thanks again for using 2CarPros.
Danny-

Thanks for advice worked perfect!

You are welcome!
Thanks for using 2CarPros.
Danny

Hi. I'm driving 2004 Optra 1.8LT Automatic. Last time I'm having the problem with fluctuated RPM during cold engine. So I brought the car to the workshop and they clean-up my throttle body (disconnect all parts related including IAC, all socket and tube) and the problem been solved

But I'm having new problem day after that. For the past 7 years, my RPM only at 800 rpm at all conditions (either when I put on gear parking/neutral or stop at traffic light and change it to neutral). But currently, the RPM high up to 2000 rpm during parking/neutral, especially when i change my gear to neutral while engines running/waiting at traffic light, or waiting my sons at his school.

How to solve it? I want it back as before, at 800 RPM. Idle Air Control Valve problem? Throttle position sensor problem?

Start by cleaning out the IACV and see what happens

Thank you. Will do as per advice.

no CEL?

may need computer re program of throttle functions.