IAC Problem: How many RPM's does your vehicle IDLE at?

[ajskyman]

Ya know, I started to grab a wrench to take it off but then I remembered that curiousity killed the cat so I backed away from the wrench. I really hate it when you take some bolts off and parts go "sprong" in different directions.

These engine where used in the Mustang back in 2002 so perhaps there was a performance part that strapped on top.

Wouldn't come off easily for me when I was perusing your fix so I stopped as well. It would be just my luck for it to come off and mess something else up haha.

Also, new rubber elbow tomorrow and going to clean the EGR valve...if not fixed, time to break out the cash and get the Motorcraft IAC!

 

[ajskyman]

Rough Idle Fix

I just wanted to give a quick update for my previous post. I ended up buying and installing the motorcraft IAC for my make and model.

The vehicle now idles like new! The only advice I would give is try cleaning your EGR port as suggest by SyberTiger because the IAC is about $80.00 and it would be a bummer to buy it and not have it fix the issue. Also, you can try cleaning your IAC which may or may not solve the issue. It did not for me, so I had to buy a new one. Hope this information helps everyone!

One last note...the IAC from Amazon.com does not come with a new gasket, or at least mine didn't. The only place I could find one was at Advance Auto Parts and even then it is hard to find. Be sure to tell the people working there that it is listed under carburetor parts...not under IAC. Either that, or buy one at the same time you buy the IAC on amazon.com.

Have a great day everyone!

 

[SyberTiger]

I just wanted to give a quick update for my previous post. I ended up buying and installing the motorcraft IAC for my make and model.

The vehicle now idles like new! The only advice I would give is try cleaning your EGR port as suggest by SyberTiger because the IAC is about $80.00 and it would be a bummer to buy it and not have it fix the issue. Also, you can try cleaning your IAC which may or may not solve the issue. It did not for me, so I had to buy a new one. Hope this information helps everyone!

One last note...the IAC from Amazon.com does not come with a new gasket, or at least mine didn't. The only place I could find one was at Advance Auto Parts and even then it is hard to find. Be sure to tell the people working there that it is listed under carburetor parts...not under IAC. Either that, or buy one at the same time you buy the IAC on amazon.com.

Have a great day everyone!

Awesome. Glad to hear you resolved the problem without giving the stealership any money.

 

[ajskyman]

Awesome. Glad to hear you resolved the problem without giving the stealership any money.

I have never heard a more perfect name for the dealership...all of my car buddies will be hearing that one!

 

[user_error098765]

Thankss for the in-depth

I cleaned out the egr and the throttle body, I'm currently replacing the iac with another new one..perhaps I got a crappy new one as well. I'll try reposting later today to see how that goes..got both from advanced auto...egr valve was working btw..if the new aic doesn't fix it..i'll move on to the throttle position sensor..also I noted that whomever worked on this car before had not put a gasket on the egr valve, so that will be replaced too. it wasn't leaking from any hoses I checked them all. I'll let you know how it pans out. I'm hoping it's just a pos iac that I got.

 

[user_error098765]

Thanks for The Original Post folks

I took SyberTigers advice (as it was well documented) I had to laugh about the stick thing I took the egr valve off cleaned it, cleaned out the throttle body, put the new gasket on, put the new aic module on, cleaned out anything I could see..and low and behold...a suprise behind the throttle set plate...(I think that's what I read on here it's called) I should know what it is, the same thing they used to have on carburetors...anyhow..a mouse had built a nest back there!! The arm was getting restricted making it act up...Ohwell...new parts can't hurt The original problem was definitely the iac though..the new one was crap..problem solved you guys rock.

 

[1988TTOP]

i wonder if this is my issue mine idles great with the aic unpluged idles at 2000rpm with it pluged in ideas

 

[user_error098765]

"i wonder if this is my issue mine idles great with the aic unpluged idles at 2000rpm with it pluged in ideas "
I would try the aic first, disconnect the battery, take it off throw it away and replace with a new one...these are notorious for failing "even out of the box apparently" (probably made in Mexico.) May as well take off the egr valve while you have everything apart anyhow and clean it out and make sure it's working. clean out the opening port hole...I just sprayed the hell out of it with carb/ choke cleaner and wiped it out. Check the back of the throttle body to where the throttle cable is attached and make sure there's no impediments to its operation. I don't know where this is supposed to be set at, I'm sure some one on here has better answers than me for that but most likely this will solve your rpm issues...mine is steady at about 7.5k - 8k now once it settles in. Hope this helps

 

[03EBVan]

thanks for the info syber
i just started having this problem noticed an erratic idle, it jumps to around 1100 then goes down to about 500 and eventually stalls itself, started happening more and more and sometimes stalls when im taking a corner and even when i was travelling about 60kph (only when not accelerating) now im driving with the 2 foot method holding the brake and giving it gas.
Took apart the IAC and cleaned it up, seemed to idle fine untill i took it for a drive and the same issues returned.
I then attempted to clean the TB and the EGR port, i cleaned up around the opening and the plate with TB cleaner, i was going to do the port hole but it looked pretty clean i could see the actual hole and the diameter with the flashlight just a tiny bit of carbon around it, so i just wiped around it a bit with a cloth on a stick.
Put it all back together and still having the same problems
When IAC is unplugged idle is around 450-500 but does not stall.
Going to replace the IAC with the motorcraft unit but i have to wait for shipping from amazon, the auto parts stores up here in Vancouver dont carry motorcraft. Hopefully after the new IAC gets in the problem will be gone??

The problem also comes and goes which is even more confusing sometimes it idles fine at 750 then at the next stop light starts acting up again.

 

[SyberTiger]

Definitely get a Motocraft IAC. Don't waste time or money with the other brands. Also, I can't recall if your 2003 has the "infamous" rubber elbow in the vacuum line system. If so, check to make sure the elbow is intact and has no holes or cracks in it.

 

[03EBVan]

is the rubber elbow the piece that goes right into the IAC?

 

[SyberTiger]

is the rubber elbow the piece that goes right into the IAC?

Actually, NO. Look at THIS THREAD. The rubber elbow would be to the right and below the IAC as shown in the picture.

 

[200KTrac]

My fix to rough idle/stall

Hey guys, Thanks to SyberTiger's multiple posts on solutions for the rough idle/stall issues. All be it, a New IAC, MAF sensor, PCV elbow, All elbows replaced etc... It progressively got worse. Finally had Midas do an "induction Service and Idle Relearn" (per bill) and that seems to have done the trick. 187$ for the service.

In general terms explained to me, they took my intake hose off, hooked up so contraption that blew threw the entire induction assembly to bust built up carbon out of the system. Took about 45 minutes. The 2001 w/201K is running like a charm now! Thanks everyone that have posted issues and solutions to the rough idle that seems to be a pretty common problem.