2002 Mitsubishi Galant - How to Check the Idle Air Control - Easy DIY Rough Idle Fix

This is the removal and installation of an idle air control sensor on a 2002 Mitsubishi galant. In many cases these sensors can be cleaned a couple times before needing full replacement. Either way you want to go, this video shows how fast and simple the removal and installation process is.

Common symptoms of a dirty or faulty IAC valve usually show up at stop lights or stop signs. Yes, rough idles can sometime indicate other issues but as you can see this is a quick and easy starting point.

In this specific case, my rough idle problem ended up being caused by a faulty spark plug boot/wire, however, in many other situations the IAC had noticable carbon buildup. For something so simple to remove / inspect, this is usually where I start when diagnosing idle issues.

Note: Yes, I am aware that the sound quality isn't great. My mic is junk but the visual is all you really need.

[albertorodriguez-vzip]

Thanks for the video. I fixed my 2003 4-cyl Galant. It'd stall at every stop. Removed it, cleaned it and.put it back.

Started by cleaning the Air intake valve removing all the dirt, which let me drive 9 miles back home.

I cleaned it again the following day, along with the IAC shown in this video. It was full of the cleaning liquid I had just used, so I congratulate myself for watching this video.

Spray the carburetor cleaner on a rag, and then rub it. Don't spray it into the Air intake valve itself, cause you'll make a pool in the IAC housing.

Great video. No words, just straight to the task at hand. Thanks bud!

[brandon_indamix]

I have a galant 02 my self and I'm having issue with my accelerating messes up while I'm driving the rpm will rise and I have to let off the gas for it to go back into place for me to keep going what could be the issue of this because I wish I was a mechanic so I'd be able to find the problem
And I always have a squeak and squeal when I start my car now:( please Any advice would be helpful thank you

[hxt]

Hey 👋 great video, do you know if this sensor will throw a code?

[hightttech]

What did we learn other than how to R&R the valve? No testing was performed whatsoever.

[officialrotorblitz]

Do you perhaps know if this will fix the following issue? I've got my Galant 2.4 GDI 2002 for like 3 weeks now and I notice that when I hit road and it warms up and I come to a stop de idle RPM dives to like 500rpm and I can feel some heavy engine vibrations when holding the gear shifter (sounds and feels like it almost wants to stall) one time I even got a engine light pop up and it put the engine in like a protection mode (Couldn't go above 2500rpm and had to push the gas pedal all the way down to build up RPM's). It had a full service at 92.000KM and the current mileage is 104.000KM

[corpuzdelacruz]

mitsubishi galant 2003 model what is the purpose of water at the throttle valve

[damon]

So reading your description on the video, you said it ended up being a faulty spark plug? How’d you come to that conclusion. I read the same thing on a forum coincidentally.

[kevingarcia]

Hey i have the same car and mine stops running after i let go of the gas.. however if i keep the gas slightly pressed it stays on.. I ordered this part.. do you think this might be the problem ? Thanks

[austinallen]

What size is the screw that holds the iac?

[duanedonaldson]

CLICKBAIT, I still see black soot in the throttle body coming past the butterfly valve, cleaning the throttle body is the first step in troubleshooting an idle problem. You did not CHECK the IAC, you only changed it, better known as SWAPTRONICS or GUESSING. You did not use a voltmeter, frequency meter, oscilloscope or check it for movement once you removed it from the throttle body. A very lame video according to its name, so sad that DIYers will come here and get nothing to help them troubleshoot their rough idle other than a guess. If you used the description for the title, that would have been a fair deal. THUMBS DOWN.