IAC Problem?

[DoverWhite]

I changed the thermostat the other day, so had to disconnect the big hose to the throttle body. I made sure everything is put back nice and snug but now, sometimes the car stalls during idle, or just idles down as low as 500 and jumps between 500-1000 like as if it's going to stall.

So, after reading on here, i think it's the IAC. i bought one off of ebay so going to install it this weekend. Is it a difficult job ? Do i replace the whole throttle body or do I replace just the IAC?

Here's a pic of the throttle body I bought on Ebay. Which part is the IAC?

http://i5.ebayimg.com/04/i/06/48/f8/28_1.JPG

[bronxbombr]

I changed the thermostat the other day, so had to disconnect the big hose to the throttle body. I made sure everything is put back nice and snug but now, sometimes the car stalls during idle, or just idles down as low as 500 and jumps between 500-1000 like as if it's going to stall.

So, after reading on here, i think it's the IAC. i bought one off of ebay so going to install it this weekend. Is it a difficult job ? Do i replace the whole throttle body or do I replace just the IAC?

Here's a pic of the throttle body I bought on Ebay. Which part is the IAC?

http://i5.ebayimg.com/04/i/06/48/f8/28_1.JPG


Was the car doing this before you changed the thermostat? I cant see the thermostat causing IAC problems? Did you plug yours MAF? Check for vacuum leaks?

[RedGalant2k1]

Do you or have you had any check engine lights?

If you bought a new IAC motor just match it up with whats on the car, but If i'm not mistaken it should be the black part just above the main part of the throttle body.

http://i37.photobucket.com/albums/e52/RedGalant2k1/TBpicture.jpg

[DoverWhite]

I didn't have this problem prior to installing the thermostat..

And the CEL is not lit, so no error codes (i also checked w/ scanner).

I'm not too familiar w/ how to check for a vacuum leak.

What's a MAF?

[SpicyGalant]

your mass air flow sensor is ur MAF.. i doubt its that cuz if it weren't connected properly your car wouldn't stay on at all. It's a plug'n'play type thing - connects to ur air intake/filter system. Um... i dont think u had to buy a new IAC- i think maybe there is something you forgot to do..like clamp something - cuz think about it - the car was fine b4 u changed the thermostat and to get to the thermostat in an 8g u gotta take out the air intake system - the battery - a few tiny hoses.... move ur wire harness a lil and bam.. so i would jus go over everything again if i were you.

[RedGalant2k1]

Did you bleed the coolant system (get the air bubbles out) after replacing the thermostat? If not you should do so, that can also cause your issue.

[DoverWhite]

No, I didn't bleed out the air out of the coolant. Wow, that would cause my car to idle and sometimes stall?

How do I go about bleeding the air out of my coolant?

[silversound]

I had the same exact problem. I had the thermostat changed and then about a week later car started having a wierd idle and the cause was the IAC motor. I am in the process of getting a new one. These Mitsus' can be wierd. https://www.thegalantcenter.org/style_emoticons/default/smile.gif

[DoverWhite]

Just curious, but how were you or they able to determine that it was the IAC?

[silversound]

I did a few searches here on the center, then i went to the dealer and had some work done and thats when they told me it was the iac motor. I called the dealer who runs the site www.mitsubishiparts.com and he gave me a great price on a new one, it's about half of what my delaer was going to charge.

[FRCFD6]

sounds like you have air in your system.

[stopfakn]

Mine does the same thing and they told me it was the iac also, I actually want to change the thermostat and bleed the system before I take it in. They're only charging $366 for parts/labor not bad

[DoverWhite]

I'm not sure I understand why my coolant system needs to be bleeded. Can someone explain?

[FRCFD6]

<div class='quotetop'>QUOTE(DoverWhite)</div><div class='quotemain'>I'm not sure I understand why my coolant system needs to be bleeded. Â* Can someone explain?</div>

cause there are bubbles caught inside the coolant where the piping is higher than the radiator fill spout.

[RedGalant2k1]

<div class='quotetop'>QUOTE(FRCFD6)</div><div class='quotemain'><div class='quotetop'>QUOTE(DoverWhite)</div><div class='quotemain'>I'm not sure I understand why my coolant system needs to be bleeded. Â* Can someone explain?</div>

cause there are bubbles caught inside the coolant where the piping is higher than the radiator fill spout.</div>

Which in turn can cause idling issues. Think of trying to talk but you got a bad case of hiccups.

[bronxbombr]

<div class='quotetop'>QUOTE(RedGalant2k1)</div><div class='quotemain'><div class='quotetop'>QUOTE(FRCFD6)</div><div class='quotemain'><div class='quotetop'>QUOTE(DoverWhite)</div><div class='quotemain'>I'm not sure I understand why my coolant system needs to be bleeded. Â* Can someone explain?</div>

cause there are bubbles caught inside the coolant where the piping is higher than the radiator fill spout.</div>

Which in turn can cause idling issues. Think of trying to talk but you got a bad case of hiccups.</div>

After awhile this makes your shit go bad.

[DoverWhite]

Can I replace just the IAC without removing the throttle body? Is it a lot of work?

[RedGalant2k1]

<div class='quotetop'>QUOTE(DoverWhite)</div><div class='quotemain'>Can I replace just the IAC without removing the throttle body? Â*Is it a lot of work?</div>

Its very easy, the IAC should be bolted or screwed to the Throttle body, and is a 5min remove and replace kind of thing.

[manybrews]

something you should know about THAT type of IAC motor.

it is NOT a "smart" IAC motor in that it does NOT know how far its actually opened.
When the battery is unhooked and then reattached for any reason, the IAC is run all the way out for about 3-4 seconds, then run all the way in. the computer "assumes" its working correctly, and starts the IAC count at zero, then goes from then when trying to adjust the idle.
If you've unplugged the IAC and had the key on for any reason, the IAC counts are incorrect.
Heres what you need to do. Unhook the battery for a few minutes. During that time, clean the throttle body VERY WELL (if you havent done it already). reattach the throttle body, then start the car (dont let the throttle cleaner stay inside the throttle body too long; IAC damage could result).
The car will sputter as it will be flooded, so hold the throttle open a bit.
It will clear itself out, and hopefull idle correctly. If it still idles poorly, a failing IAC is a definate culprit, but there are other possibilities.

[DoverWhite]

http://i37.photobucket.com/albums/e52/RedGalant2k1/TBpicture.jpg[/quote]

Cool you guys, thanks! I replaced the IAC (circled in red), it was fastened w/ 3 tiny little phillips screws. I'll drive it around for a few days and see how it does.

Should I reset my computer by unplugging the battery ?

[silversound]

SO DoverWhite ho is she runnin?

[DoverWhite]

Just got home, so far so good.. but not holding my breathe just yet because the last time I tried a few things it lasted a couple of days before acting up.

I had to reset the computer by unplugging battery for 1/2 hour, because prior to reset'ing the idle was too high (1100rpm) and tranny shifted wierd.. it just seemed like some sort of timing was off. After reset, all is well.

If no problems by the end of the week, I'll feel satisfied.

[DoverWhite]

Ok guys, 3rd day and everything is running smoooooth.

So I'm pretty confident (75%) that it's solved.

I can not definitively say that changing the IAC solved it though, as i did experience the same idle problems after installing it. It is only after I reset the computer (by unplugging battery for 20 minutes) did it truly resolve all issues.

So it IS possible that the IAC solved it, or a combination of the both, or even possible that the resetting of the computer alone could have done it (I never tried resetting battery alone, prior to installing the IAC).

With that in mind, thank you everyone for your kindness and help. If not for the tips on this board, I would've SURELY and REGRETTABLY spend probably nearly 1k to have the dealer diagnose and fix this. I ended up spending only $50 for the IAC and less than 1 hour of my own labor.

You guys are the best.

[FRCFD6]

nm