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  • SN95 4.6L Mustang Tech

It's been a week. STILL have high idle, hanging idle.

  • Thread starter Thread starter supergoat
  • Start date Start date Jan 18, 2007
S

supergoat

New Member
Dec 28, 2006
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Jan 18, 2007
#1
  • Jan 18, 2007
  • #1
I installed a UPR Plenum and BBK TB.

I had a VERY high idle after. I found that the culprit was the throttle plate was not closed fully. I closed it and it helped. I also did the copper cap mod and got a pretty steady idle. But it still idles at 1200 and I get code P0507. I can't find any leaks, the TB is fully sealed and it's not a bad IAC as I didn't have an issue until after doing this mod.

I'm going to do the following tomorrow.

Unplug the IAC elec. connection. Adjust the throttle stop screw until the car either stalls or damn near, remove the copper cap and reset the computer. The TPS does not allow for adjustment, I can't move it side to side at all.

Anything else to look for?
 

Cobra123089

Member
Sep 30, 2006
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7
Broomfield CO/ Laramie WY
Jan 18, 2007
#2
  • Jan 18, 2007
  • #2
Did you reset the battery after initial install? If you did i would check your TPS i accidentally broke mine after putting mine back together and it lead to some of the same problems.
 
S

supergoat

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Dec 28, 2006
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Jan 18, 2007
#3
  • Jan 18, 2007
  • #3
Yea I had the battery disconnected as I installed everything. I inspected the TPS and it appears to be good. I was quite careful when removing and reinstalling it.
 

Cobra123089

Member
Sep 30, 2006
94
0
7
Broomfield CO/ Laramie WY
Jan 18, 2007
#4
  • Jan 18, 2007
  • #4
i though i was to but i broke the spring in it. I think mine threw a code tho, it did as i remember and everytime i cleared the code the car would die. maybe someone else will come in with some input.
 
S

supergoat

New Member
Dec 28, 2006
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Jan 18, 2007
#5
  • Jan 18, 2007
  • #5
Yea, the only code I have is P0507 which is "Idle RPM higher than expected"
 

COramprat

...I can take it. I think.
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Jan 18, 2007
#6
  • Jan 18, 2007
  • #6
Where are you located?
 

mrvax

Stay thirsty my friends
Founding Member
Nov 29, 1999
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SN Moderator: Orlando, Fl.
Jan 18, 2007
#7
  • Jan 18, 2007
  • #7
Try calling BBK and ask them what is the most common cause.
 
S

supergoat

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Dec 28, 2006
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Jan 18, 2007
#8
  • Jan 18, 2007
  • #8
COramprat said:
Where are you located?
Click to expand...


York, PA.
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
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Sea of Tranquility
Jan 19, 2007
#9
  • Jan 19, 2007
  • #9
supergoat said:
York, PA.
Click to expand...
Ah...too far away.

Lemme see if I can explain the problem I had.

Same hanging idle and code you have. The blade on the TB manupulates the TPS by resting in the prongs inside of the sensor. With you finger (pinkie slides in OK) manipulate the prongs to see which way the spring loaded cylinder rotates the most. Place the sensor over the blade and you can tell if it will rest on said prongs. If it doesn't you may need to place the sensor at an angle, making sure the blade will rest on the prongs inside of the sensor, ensuring it rotates the right direction and turn the entire piece until the screw holes line up.

What was happening with mine is the TB blade that manipulates the sensor was just rotating and not engaging the prongs, therefore the sensor was not functioning at all.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
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89
the people's republic of massachusetts
Jan 19, 2007
#10
  • Jan 19, 2007
  • #10
the most common cause of this code is a vacumm leak or a intake leak after the MAF sensor. also check the egr valve area and make sure it's not leaking vacumm there.

Does the engine surge or is the idle steady? If you have access to a scan tool that provides live data look at your long term and short term fuel trims and MAF voltage.
 
S

supergoat

New Member
Dec 28, 2006
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Jan 20, 2007
#11
  • Jan 20, 2007
  • #11
The idle is steady unless I have the defrost/ac on, then is surges a bit.

Thanks for the TPS tip, I checked and it's good.
 

joshheat25

Member
Nov 8, 2004
871
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16
Delaware
Jan 20, 2007
#12
  • Jan 20, 2007
  • #12
I know this sounds dumb but make sure you have the idle screw as low as it can go! and also I had a problem with this I tightned the Upper intake plentum too tight. I bought a new gasket and didn't tighten the new one down as much and I haven't had any problems. But My idle wasn't high just surged.. And Where are you located? If it is cold out I know it takes my car a very long time to get warm and the idle is always high....
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Jan 20, 2007
#13
  • Jan 20, 2007
  • #13
joshheat25 said:
I know this sounds dumb but make sure you have the idle screw as low as it can go! and also I had a problem with this I tightned the Upper intake plentum too tight. I bought a new gasket and didn't tighten the new one down as much and I haven't had any problems. But My idle wasn't high just surged..
Click to expand...
Many have suggested you should never adjust the idle screw. I may be wrong but I don't think you want to touch it.

And Where are you located? If it is cold out I know it takes my car a very long time to get warm and the idle is always high....
Click to expand...
supergoat said:
York, PA.
Click to expand...
 
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