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Severe idle problems after TB/Plenum/O/R X-pipe install

  • Thread starter Thread starter ThrowedOff
  • Start date Start date Apr 17, 2007
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ThrowedOff

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Nov 16, 2006
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Apr 23, 2007
#21
  • Apr 23, 2007
  • #21
Well, of course, the problems came back... Started the car up today and it was giving me problems instantly.

I don't understand how the hell I can go 65mi with no problems, then have problems again all of the sudden.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
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Apr 23, 2007
#22
  • Apr 23, 2007
  • #22
Any time you make changes to the intake you need to be restting the PCM. If during the course of your troubleshooting you are not resetting it after each change then you are just wasting your time, kinda like you wasted your money on a POS aftermarket TB...

Also your DIY MIL eliminators are probably not helping...
 
T

ThrowedOff

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#23
  • Apr 23, 2007
  • #23
Kilgore Trout said:
Any time you make changes to the intake you need to be restting the PCM. If during the course of your troubleshooting you are not resetting it after each change then you are just wasting your time, kinda like you wasted your money on a POS aftermarket TB...

Also your DIY MIL eliminators are probably not helping...
Click to expand...

I am resetting the computer each time... Also, I figured the TB would be decent, being MAC and all.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 24, 2007
#24
  • Apr 24, 2007
  • #24
hotmustang331 said:
What is the "hole" in the TB blade that you speak of? My BBK TB has no such hole and I have missing problems @ very light throttle input between 1000-1700RPMs....and the same RPM at slightly heavier throttle loads has 0 miss. Wonder if thats whats causing it .


So yea TS see if your TB blade has a hole in it...if not, maybe thats your issue.
Click to expand...

it's there to smooth the transition from closed throttle to part throttle. If the car runs better witht he stock TB then drill a hole the exact same size in the aftermarket TB
 
G

GSP

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Apr 8, 2004
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Huntsville, Alabama
Apr 24, 2007
#25
  • Apr 24, 2007
  • #25
Easy fix, been there done that.

Disconnect the AIC, adjust the throttle body idle screw to get you a good idle, shut it off, disconnect the battery, plug in AIC, reconnect the battery,,,done
 
T

ThrowedOff

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#26
  • Apr 24, 2007
  • #26
GSP said:
Easy fix, been there done that.

Disconnect the AIC, adjust the throttle body idle screw to get you a good idle, shut it off, disconnect the battery, plug in AIC, reconnect the battery,,,done
Click to expand...

Unfortunately I'm thinking it's not the idle, as sometimes the car idles fine for tens of stops in a row. Plus, I have problems off-idle sometimes.
 
G

GSP

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Apr 24, 2007
#27
  • Apr 24, 2007
  • #27
What ever man.

What I told you will fix this problem:

"It's very random, sometimes at a stop the car will repeatedly drop to ~200rpm and then rev up to 1500, sometimes it will die completely while doing this. Sometimes it will sputter while driving at 1300rpm."

This up and down is the AIC trying to make idle....

Yes you might have other problems, but ANYTIME you replace the throttle body you must set the idle mechanically before the AIC will work.

Good luck
 
K

Kilgore Trout

Fried or Broiled ?
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Mar 30, 2005
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#28
  • Apr 24, 2007
  • #28
And by AIC you of course mean IAC...
 
T

ThrowedOff

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#29
  • Apr 24, 2007
  • #29
GSP said:
What ever man.

What I told you will fix this problem:

"It's very random, sometimes at a stop the car will repeatedly drop to ~200rpm and then rev up to 1500, sometimes it will die completely while doing this. Sometimes it will sputter while driving at 1300rpm."

This up and down is the AIC trying to make idle....

Yes you might have other problems, but ANYTIME you replace the throttle body you must set the idle mechanically before the AIC will work.

Good luck
Click to expand...

I'll try it, but I'm not too optimistic... We'll see though. I'm assuming that you meant IAC like Kilgore said?
 
G

GSP

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Apr 25, 2007
#30
  • Apr 25, 2007
  • #30
I have always refereed to it as the: Automatic Idle Controller but it is:IDLE AIR CONTROL VALVE (IAC)
 

hotdog71

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Dec 8, 2004
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Seattle, Eastside
Apr 25, 2007
#31
  • Apr 25, 2007
  • #31
GSP said:
What ever man.

but ANYTIME you replace the throttle body you must set the idle mechanically before the AIC will work.

Good luck
Click to expand...

Setting the Idle mechanically before the IAC will work sounds like to me

In fact with BBK hardware they tell you not to Touch the Idle since its preset at the factory!
Maybe this is different for cheaper manufactures!?
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Apr 25, 2007
#32
  • Apr 25, 2007
  • #32
I think drilling teh hold in the TB like SVT said will do the trick....now just to find my stock TB. I CANT FIND IT!
 
T

ThrowedOff

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Nov 16, 2006
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Apr 26, 2007
#33
  • Apr 26, 2007
  • #33
hotmustang331 said:
I think drilling teh hold in the TB like SVT said will do the trick....now just to find my stock TB. I CANT FIND IT!
Click to expand...

I may try this and see...

If I do it to mine, I'll measure where the stock hole is and what size bit to use and let you know.
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Apr 26, 2007
#34
  • Apr 26, 2007
  • #34
Thanks bud! I would greatly appreciate it if you do try this. . Iv had this problem for the past 25000 miles and just lived with it...so to now have a fix right around the corner definatly gives me alot of hope.
 
T

ThrowedOff

New Member
Nov 16, 2006
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Apr 30, 2007
#35
  • Apr 30, 2007
  • #35
GSP said:
What ever man.

What I told you will fix this problem:

"It's very random, sometimes at a stop the car will repeatedly drop to ~200rpm and then rev up to 1500, sometimes it will die completely while doing this. Sometimes it will sputter while driving at 1300rpm."

This up and down is the AIC trying to make idle....

Yes you might have other problems, but ANYTIME you replace the throttle body you must set the idle mechanically before the AIC will work.

Good luck
Click to expand...


Oh by the way, I did this, and like I anticipated, it didn't help at all.
 
T

ThrowedOff

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Nov 16, 2006
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May 4, 2007
#36
  • May 4, 2007
  • #36
I just got my SCT Xcal2 in and loaded a tune, and it dropped the P0136 code.

I'm still left with the P1151 and P1131

Any ideas what to do now?
 

Demonoid

New Member
Apr 29, 2007
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May 4, 2007
#37
  • May 4, 2007
  • #37
go get your car tuned.you cant just throw parts on the car and expecpt it to work like it did stock!!!!..get rid of the home made mills...and get your car tuned by somebody that knows what their doing!!!
 
T

ThrowedOff

New Member
Nov 16, 2006
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May 4, 2007
#38
  • May 4, 2007
  • #38
Demonoid said:
go get your car tuned.you cant just throw parts on the car and expecpt it to work like it did stock!!!!..get rid of the home made mills...and get your car tuned by somebody that knows what their doing!!!
Click to expand...

I just loaded a custom tune by Brenspeed and shut off the rear o2s... Still getting codes (these are for upstream o2s)
 

heyzuess

New Member
Sep 15, 2005
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May 4, 2007
#39
  • May 4, 2007
  • #39
Have any exhaust leaks?

My car was overall running poorly, especially idling bad and stalling. Turns out I had leaks at the the header collector (to the x pipe just behind the o2's) and once that was fixed it started running like a champ again.
 
T

ThrowedOff

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Nov 16, 2006
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May 5, 2007
#40
  • May 5, 2007
  • #40
heyzuess said:
Have any exhaust leaks?

My car was overall running poorly, especially idling bad and stalling. Turns out I had leaks at the the header collector (to the x pipe just behind the o2's) and once that was fixed it started running like a champ again.
Click to expand...

No exhaust leaks that I know of, also checked for vacuum leaks several times and found none.

I'm gonna pick up a new o2 sensor in the morning and see if I can't get one or both codes to go away.

I guess if that doesn't work, I'll be taking the plenum and TB back off and checking extremely thoroughly for leaks
 
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