IAC sound ?

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dutch animal
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IAC sound ?

Post by dutch animal » Sat Sep 04, 2010 10:51 am

he there.

my neon is having a little bit of a rough time.
idle's pretty rough, and stutters when im low on rpm 1500 and give it half throttle.

now i was beeing busy on the car, when i noticed something.

watch and turn the volume up :

http://www.youtube.com/watch?v=u7cUDoFLEAA

that's the IAC ???

i took it of to have a look ... but doesn't look that bad to me ??

Image

is this normal ????
and could this be the problem on the idle and stutter aswel ?

thanks
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dutch animal
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Post by dutch animal » Sat Sep 04, 2010 12:49 pm

now i've cleaned the IAC ... it gives a code: P 0508 Idle air contol motor circuit input below acceptable current.

???? i am know resseting the pcm ... so in 15 min i'll know if the code keeps comming up :(
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dutch animal
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Post by dutch animal » Sat Sep 04, 2010 1:22 pm

code's gone :D

but the sound of the IAC is still there.

whit a little effort you can maken music with it now.

idle .... brrrrrrrrrrr ( bas like )
led lights on breeeeee ( like midtone )
headlights on brriiiiiiiiiiiiii ( like tweeter )

ok .. butt who is gonna help me out here ???

pretty please :(
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occasional demons
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Post by occasional demons » Sat Sep 04, 2010 1:57 pm

Sound is normal.


Rough idle and stuttering are either a need for a tune up, or other problems. The IAC motor only will make it idle too low, (below 750 rpm), or too high (above 900 rpm).

If it is rough above 850 to 1000 rpm, there is some other problem.
Bill
Probably shouldn't listen to anything your penis says, that guy's a dick.
Patience, of course, is a very powerful weapon, but sometimes I start to regret that it is not a firearm.
Too much time spent here is a sign of a bad case of Ownaneonvirus.

2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap

dutch animal
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Post by dutch animal » Sat Sep 04, 2010 2:24 pm

the idle is never the same ... cold about 1000 rpm, hot about 7/800 rpm... when comming to a stop, 1200 rpm ... and when it's out of motion ... idle back to normal ... but car shaking :(

so the noise of the iac is always there ???
i thought it was suppose to make noise 2 sec and then by silent ?

"tune up" ... could you please explane "tune up"
dutch guy, having trouble with language :)
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occasional demons
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Post by occasional demons » Fri Sep 10, 2010 4:47 pm

A basic "Tune Up" means new spark plug wires, spark plugs, cleaning the IAC motor, removing TB and cleaning the inside with a soap based cleaner.

You could/should also use some Mopar Combustion Chamber Cleaner or equivalent, before changing the spark plugs.
Bill
Probably shouldn't listen to anything your penis says, that guy's a dick.
Patience, of course, is a very powerful weapon, but sometimes I start to regret that it is not a firearm.
Too much time spent here is a sign of a bad case of Ownaneonvirus.

2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap

OB
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Post by OB » Fri Sep 10, 2010 9:49 pm

If the idle is high when you come to a stop, I'd say there's something holding the throttle open slightly. Reason I say that is because that's exactly what happened to mine after I adjusted the idle control screw on the throttle body a little too close to the threshold. The PCM will use the IAC to lower idle airflow after a couple of seconds to combat this, and eventually my PCM "learned" that the throttle plate was flowing too much and the problem went away. Comes back every time I disconnect the battery, further proving that the computer was able to adjust fuel trims permanently within a few trips.

There are a couple possibilities. Either the throttle plate is binding in the body somehow, the throttle return spring isn't doing it's job right, or the idle screw is out of adjustment. If none of those are apparent, you might just have some other issue altogether. A tune up would be a good place to start, as stated above.
-Derek

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occasional demons
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Post by occasional demons » Sat Sep 11, 2010 12:06 am

I think it idles at "normal" rpm's at rest, he was just saying it was higher during coasting to a stop. Which is a normal condition. Tho 1200 is just a tad bit high. I think 1000 rpm coasting is the norm.

The tune up may help the shaking, but also check the torque strut alignment, and bushing condition. Getting a glass smooth idle from these is not an easy feat. There will always be some vibration, it mostly comes down to how well you tolerate it, and what your expectations are. Just remember, it is an economy 4 cylinder engine, not a luxury class V8.

I know if I had solid strut bushings, mine would get annoying after a while.
Bill
Probably shouldn't listen to anything your penis says, that guy's a dick.
Patience, of course, is a very powerful weapon, but sometimes I start to regret that it is not a firearm.
Too much time spent here is a sign of a bad case of Ownaneonvirus.

2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap

dutch animal
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Joined: Sun Nov 15, 2009 9:24 am

Post by dutch animal » Sat Sep 11, 2010 4:24 am

i have al the bushings replaced for prothane bushings .. and motormount inserts .. so a bid shaking is no prob ...

i have been playing with the idle screw .. so that could be a bit out of tune.

new plugs are 1 for +- 2 month now.

iac cleaned 1 weak ago.

new spark wires and coil tommorow.

i must say, with cleaning of the iac things with the idle went a LOT better .. just need to adjust screw now i think.

the stutter is becomming really bad now , so hope the new wires and coilpack will do that trick.

thanks for explaning the "tune up" thing ... tommorow i'll cleane every thing and instal new parts .. so update by then .. hoping it'll salve the probs.

i'm glad that the IAC sound is normal .. never heard it before .. so scared the sh*t out of me LOL
( been searching for a week, finding out its normal LOL )

thanks so for ;)
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Jenni
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Re: IAC sound ?

Post by Jenni » Sat Sep 11, 2010 5:01 am

dutch animal wrote: i took it of to have a look ... but doesn't look that bad to me ??

Image

is this normal ????
your iac looks shocked like little Kevin home alone!

Image

dutch animal
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Post by dutch animal » Sat Sep 11, 2010 8:09 am

DAMN !!!!! your right ... maybe it's just missing it's IAC parents ;)
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Jenni
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Post by Jenni » Sat Sep 11, 2010 8:17 am

but now how to check it: clean it and press your lips on the upper hole - blow air in.
Can you or can you not?
If you can - the iac is fucked up (or better said: the seals inside).
Please recheck that with another Neon, i am not sure if the 2.0 uses the same technic...

But 3 other culprits: TPS, TPS wiring, IAC wiring. A loose wire can bring you some sleepless nights!

dutch animal
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Post by dutch animal » Sat Sep 11, 2010 9:25 am

heee .. i didn't know about that trick .. will try that tomorrow :)

i hope and bet it's the spark wires .. been there for a long time now ;)

i'll post what i can find out ;)
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dutch animal
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Post by dutch animal » Sat Sep 11, 2010 4:25 pm

ok .. cleaned the TB and intake .. with wynn's DIP 3

nice stuff .. did a good job on the idle ...
butt stutter stil there (not that i was really thinking a little spray would prevent that but you never know ;) )

tomorrow, sparkwires and coilpack ;)
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dutch animal
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Post by dutch animal » Mon Sep 13, 2010 1:03 pm

ALL PROBLEMS ARE SOLVED !!!!

it turned out to be the spark wires ;)

now i know how a neon "should" drive and feel like :) :)

i think the wires where bad al along ..
new wires thanks to a neon friend of ours ... idle's perfect ... no stutter what so ever ... and when i turn my airco on .. it doesn't shake that much anymore :D

thanks for the help guys , i'm glad it al turned out to be a little thing like this ;)
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Fuzzyneon
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Post by Fuzzyneon » Mon Sep 13, 2010 2:12 pm

hate it whena bunch of little problems come up hard to troubleshoot sometimes glad shes fixed!
Member of Spork Racing
2002 Dodge Neon
Frankenstien



dutch animal
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Post by dutch animal » Mon Sep 13, 2010 2:27 pm

thanks ;)

indeed ... like carsten said ... a loos wire can couse sleepless nights :(
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gcretro
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Post by gcretro » Thu Aug 02, 2012 11:28 am

OB wrote:If the idle is high when you come to a stop, I'd say there's something holding the throttle open slightly. Reason I say that is because that's exactly what happened to mine after I adjusted the idle control screw on the throttle body a little too close to the threshold. The PCM will use the IAC to lower idle airflow after a couple of seconds to combat this, and eventually my PCM "learned" that the throttle plate was flowing too much and the problem went away. Comes back every time I disconnect the battery, further proving that the computer was able to adjust fuel trims permanently within a few trips.

There are a couple possibilities. Either the throttle plate is binding in the body somehow, the throttle return spring isn't doing it's job right, or the idle screw is out of adjustment. If none of those are apparent, you might just have some other issue altogether. A tune up would be a good place to start, as stated above.
I have the idle hanging surging from 1K to about 1400 when coming to a stop. I did mess with the idle screw about a year back..

Now how does one ensure it is set correctly? just trial & error?

dutch animal
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Post by dutch animal » Thu Aug 02, 2012 11:42 am

jups ... thats what i did anyway :))
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occasional demons
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Post by occasional demons » Thu Aug 02, 2012 1:26 pm

IIRC, the TPS voltage is from 0.6 to 3.9 volts from closed to WOT. So if you back probe the connector, and turn the idle screw so it reads around 0.6 volts, you should be good.
Bill
Probably shouldn't listen to anything your penis says, that guy's a dick.
Patience, of course, is a very powerful weapon, but sometimes I start to regret that it is not a firearm.
Too much time spent here is a sign of a bad case of Ownaneonvirus.

2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap

gcretro
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Joined: Tue Jan 25, 2011 4:01 pm

Post by gcretro » Thu Aug 02, 2012 1:44 pm

occasional demons wrote:IIRC, the TPS voltage is from 0.6 to 3.9 volts from closed to WOT. So if you back probe the connector, and turn the idle screw so it reads around 0.6 volts, you should be good.
Awesome! and I can open it up till the TPS registers a bump. Dumb q: And this should be done with Key ON I would think.

occasional demons
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Post by occasional demons » Thu Aug 02, 2012 2:09 pm

Yes key on, so you have 5 volts going to it.

One wire will be 5 volts +, one ground, and one variable to ground. You want the ground and variable to measure across. I can't recall what colors are what, but it shouldn't be too hard to figure out.
Bill
Probably shouldn't listen to anything your penis says, that guy's a dick.
Patience, of course, is a very powerful weapon, but sometimes I start to regret that it is not a firearm.
Too much time spent here is a sign of a bad case of Ownaneonvirus.

2000 Neon MTX swap with '02 R/T PCM
1999 neon coupe 2.4 swap

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