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Just replaced IAC and idle hunting is back after one day. by Lou and Blue
Started on: 05-06-2014 02:06 PM
Replies: 21 (743 views)
Last post by: countach711 on 11-08-2014 06:37 PM
Lou and Blue
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Report this Post05-06-2014 02:06 PM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
Replaced IAC with a $10 eBay one this past Sunday. Yesterday (Monday) the idle hunting came back just the same as before. Bummer. I didn't think Rodney's IAC socket was to an be used again, but now I do need to use it again. I don't know if a better IAC replacement is needed or if I didn't clean the hole out enough. I couldn't really get any kind of brush in there to clean it out. When I stuck my pinky in there, there was carbon buildup. Rodney's socket sure made it easy to remove though! "Rodney to the rescue" should be his username.
Could the idle hunting possibly be something else?
My ECM buzzes when going to idle, maybe something funky in there?

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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hdryder
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Report this Post05-08-2014 07:42 AM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Along with the hunting idle, do you have any motor shake that is most apparent at idle?

I have replaced my IAC at the suggestion of a local repair shop to resolve hunting and rough idle, but I still have not fixed the problem with my '87 GT 5-speed.
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2.5
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Report this Post05-08-2014 09:12 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
My guess is more likley TPS. No service engine lights for that? I have had them failing without a light, though that was on a 2.5.

[This message has been edited by 2.5 (edited 05-08-2014).]

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MulletproofMonk
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Report this Post05-08-2014 10:09 AM Click Here to See the Profile for MulletproofMonkClick Here to visit MulletproofMonk's HomePageSend a Private Message to MulletproofMonkEdit/Delete MessageReply w/QuoteDirect Link to This Post
Could be a lot of things, EGR, TPS, Vac Leak, and even a bad ground...
http://www.fiero.nl/forum/Forum2/HTML/125366.html

I can't find the article on adding the extra ground, but I believe this is the picture.

------------------
-Brian

My 87 GT Poly Suspension Upgrade (all pics) thread
Removing the roof panel
My HUD install thread
Modified stock air canister and base to 3.5 inch for 3800na

Isn't it strange that after a bombing, everyone blames the bomber, his upbringing, his environment, his culture, his mental state but … after a shooting, the problem is the gun?

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Lou and Blue
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Report this Post05-08-2014 10:16 AM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
I replaced the tps at the same time. I do need to add that extra ground wire. It's weird it only happens some times at specific temperature ranges.

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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2.5
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Report this Post05-08-2014 10:34 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Weak coil?
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Lou and Blue
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Report this Post05-08-2014 10:36 AM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well, I will be replacing if the coil with the MSD blaster
Coil someday soon , but it does run fine while accelerating.
Hopefully it just needs a cleaning out of the iac orifice.

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

[This message has been edited by Lou and Blue (edited 05-08-2014).]

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hdryder
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Report this Post05-08-2014 12:57 PM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou and Blue:

it does run fine while accelerating.


Along with the hunting idle, do you have any motor shake that is most apparent at idle?
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Lou and Blue
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Report this Post05-08-2014 01:56 PM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
Not really , not that I've noticed anyway.

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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Gall757
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Report this Post05-08-2014 04:29 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just for the record.....here is the thread on grounding straps.

EVERYONE with a V6, plase read

[This message has been edited by Gall757 (edited 05-08-2014).]

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Lou and Blue
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Report this Post05-08-2014 07:46 PM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yeah , I need to do that extra ground. My main neg cable goes to the dogbone bracket and its painted black. Gonna try that.
 
quote
Originally posted by MulletproofMonk:

Could be a lot of things, EGR, TPS, Vac Leak, and even a bad ground...
http://www.fiero.nl/forum/Forum2/HTML/125366.html

I can't find the article on adding the extra ground, but I believe this is the picture.





------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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MulletproofMonk
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Report this Post05-08-2014 11:36 PM Click Here to See the Profile for MulletproofMonkClick Here to visit MulletproofMonk's HomePageSend a Private Message to MulletproofMonkEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou and Blue:
Yeah , I need to do that extra ground. My main neg cable goes to the dogbone bracket and its painted black. Gonna try that.


Then you want that extra ground strap to go from the motor to where it is on the dogbone. Doesn't do any good to ground it to the battery tray if the battery doesn't ground there...
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mitchjl22
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Report this Post05-08-2014 11:58 PM Click Here to See the Profile for mitchjl22Click Here to Email mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
You could have a small vacuum leak. Its hard to diagnose without a smoke machine, but maybe try making one and testing it. You could use carb cleaner as well and spray around the intake and see if you get a noticeable increase in engine speed around a certain spot.

You Get the idea, it forces smoke out of the leaks, allowing you to find them.


-Mitch

------------------
My Car - 87' GT 3800sc
http://www.fiero.nl/forum/F.../HTML/121571.html#p0

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Lou and Blue
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Report this Post05-09-2014 09:41 AM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
I noticed it does run rough at idle. Kinda noticed that today, maybe because I was looking for it and criticizing the idle more than before.

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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Lou and Blue
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From: Baldwin,NY,USA
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Report this Post05-09-2014 09:42 AM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post

Lou and Blue

1349 posts
Member since Dec 2013
 
quote
Originally posted by MulletproofMonk:


Then you want that extra ground strap to go from the motor to where it is on the dogbone. Doesn't do any good to ground it to the battery tray if the battery doesn't ground there...


The neg cable also has a small wire that goes to the battery bracket too, but I think the dogbone connection would be better because that's where the thicker cable goes to.

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

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Formula88
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Report this Post05-09-2014 09:47 AM Click Here to See the Profile for Formula88Send a Private Message to Formula88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Is your replacement IAC new or used? Do you know it's good?
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avidflyr
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Report this Post05-09-2014 11:22 AM Click Here to See the Profile for avidflyrClick Here to Email avidflyrSend a Private Message to avidflyrEdit/Delete MessageReply w/QuoteDirect Link to This Post
I went thru this problem on my 88 Gt (automatic). Replaced IAC, TPS, OXy Sensor, Vacumn leak check, Cleaned Throttle Body. New Plenum Gasket, R&R Spark System....Nada
Code check showed weak signal at Temp sender to ECM (under thermostat housing ). Changed temp sender and...WALA... Idles at 700...good off idle response.
I have already added 2 extra ground wires.
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Lou and Blue
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Report this Post05-09-2014 12:50 PM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'm thinking it may just be the ground issue b/c my stock radio gets louder and lower without touching it. Kinda spooky. My temp gauge seems to work but I don't think the temp sensor is even hooked up. There's a sensor with no wire going to it. It's on the back bottom of the block. I dont even see a wire that would hook to it. Maybe that's just for the dash light for temp though.
I acquired another ECM yesterday but the guy did t know what year it was from or if its for a manual or auto. No stickers on it either, just wrinkly black paint coated.
------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
Where driving hard is SOP.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way.
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
The "DuetLorean"
VIN #5835
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Carbed and loving it! (Peugot 604 manifold) ---"Sorry purists"

[This message has been edited by Lou and Blue (edited 05-09-2014).]

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WKDFIRO
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Report this Post05-09-2014 01:32 PM Click Here to See the Profile for WKDFIROClick Here to Email WKDFIROSend a Private Message to WKDFIROEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sounds more like a small vacuum leak. EGR tube would be the first place to look.

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Lou and Blue
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Report this Post11-07-2014 05:21 PM Click Here to See the Profile for Lou and BlueClick Here to Email Lou and BlueSend a Private Message to Lou and BlueEdit/Delete MessageReply w/QuoteDirect Link to This Post
Turns out it WAS the TPS. Sorry not to update sooner. (Months ago :P)

------------------
===Always trying to find time to work on cars===
Louis Duet
Baldwin, Long Island, NY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Blue" <= '85 Fiero GT
Stock V6---Stock everything. Trying to keep it 'mostly' that way. But I just got the 3800sc to swap into it!
~~~~~~~~~~~~~~~~~~~~~
"Boo" <= '81 Delorean DMC-12
VIN #5835
"Don't hate ... Carburate!"
Stock PRV engine
Robertson Equipped
Neiland/Delman Engineered
Peugot 604 Intake manifold
Exhaust headers
Anti-3rd brake light

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Report this Post11-07-2014 06:32 PM Click Here to See the Profile for PonnariSend a Private Message to PonnariEdit/Delete MessageReply w/QuoteDirect Link to This Post
Here is the link to the article about grounding on the v6 Fiero's. Great article, very helpful.
EVERYONE with a V6 please Read by $Rich$


------------------
"Because in a split second, It's gone"

Ayrton Senna

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countach711
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Report this Post11-08-2014 06:37 PM Click Here to See the Profile for countach711Click Here to visit countach711's HomePageClick Here to Email countach711Send a Private Message to countach711Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou and Blue:

Well, I will be replacing if the coil with the MSD blaster
Coil someday soon , but it does run fine while accelerating.
Hopefully it just needs a cleaning out of the iac orifice.


Here's what I got at Amazon, Accel Super Coil, $30 shipped http://www.amazon.com/gp/pr...00_s00?ie=UTF8&psc=1
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