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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

new intake and tb problems

  • Thread starter Thread starter sc_mustang
  • Start date Start date Aug 2, 2005
S

sc_mustang

New Member
Jun 7, 2004
3
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1
Aug 2, 2005
#1
  • Aug 2, 2005
  • #1
I just got a accufab intake and 75 mm tb put on today and the rpms go up fine but when they come down it stops at about 1 1/2 then drops to 1,I tried resetting the computer but still dose the same thing.anyone know anything about it? thanks
 
C

Chopper1

New Member
Jan 2, 2005
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Wv
Aug 2, 2005
#2
  • Aug 2, 2005
  • #2
It could be an intake leak but you can look for it later.To cure part of the "hanging revs" problem,drill a 3/16" hole in a 1/2 copper pipe cap.Pull the IAC hose off the T/B and stick the cap inside.Put the hose back on and start the car.If the car won't idle with the A/C on remove the cap and enlarge the hole to 1/4".This should allow the car to idle at about 900 rpm's.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
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Dunedin, FL
Aug 2, 2005
#3
  • Aug 2, 2005
  • #3
After resetting the computer, you'll have to give it 5 days or so...it WILL get better. Been there, done that.
If it's sitting at 1000 RPMs at idle (and stays there), you'll need to loosen the TPS screws (slightly) and twist the unit counter-clockwise to bring the idle down a bit. I do this with the engine running and essentially set the idle by ear first, then ck the tach.
 
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wackit1

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Aug 3, 2005
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Aug 3, 2005
#4
  • Aug 3, 2005
  • #4
SC_MUSTANG - Just wondering if tried the suggested fixes to your high idle problem after your TB install. I'm experiencing a similar problem.
 

Mossberg

Active Member
Jul 21, 2003
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1
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ATL, Shawty
Aug 3, 2005
#5
  • Aug 3, 2005
  • #5
Def sounds like Throttle Position Sensor (TPS) if your idle only goes to 1.1K.
 

DEEPSEAGT

New Member
Dec 29, 2002
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San Diego
Aug 10, 2005
#6
  • Aug 10, 2005
  • #6
Same boat here. TPS set to 98 bored out tps top hole to get there.

IAC may be dirty doubt it. vacume leak poss doubt it. I heard that this is common for ACCUFAB?? Can I live with 1000 RPM at Idel maybe. Pehaps I'll try the copper cap thing is it a Cap or tube??

later
 

DEEPSEAGT

New Member
Dec 29, 2002
178
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San Diego
Aug 13, 2005
#7
  • Aug 13, 2005
  • #7
1000 rpm

sc_mustang said:
I just got a accufab intake and 75 mm tb put on today and the rpms go up fine but when they come down it stops at about 1 1/2 then drops to 1,I tried resetting the computer but still dose the same thing.anyone know anything about it? thanks
Click to expand...


get that bad boy working right/

goingb to HD right now to get copper plug.

my vac was at 18
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
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Dunedin, FL
Aug 13, 2005
#8
  • Aug 13, 2005
  • #8
Did you mix up/swap the two hoses that go to the intake tube?
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
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Sea of Tranquility
Aug 13, 2005
#9
  • Aug 13, 2005
  • #9
I betting on the TPS too. Remove the sensor and make sure the TB blade is resting on the prongs of the sensor. Could be the TB is just rotating around inside the sensor but not manipulating the sensor. That will cause the RPM's to hang.
 
0

'03GTinFLA

Member
May 29, 2004
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St. Petersburg, FL
Aug 14, 2005
#10
  • Aug 14, 2005
  • #10
I know a guy, who know's a guy that crossed the two intake tubes when he was installing his Accufab 75mm TB and plenum. All kinds of idle problems. It would run about 1.5-2k and hang bad. He tried the copper pipe mod, then bored out both holes on his TPS, adjusted idle setting with his Predator and nothing fixed it. Then he just stopped and looked at his engine and realized his error. Now it runs great.
I would say first double check all your connections and make sure they are all on correctly. Then try the copper cap thing. If still nothing then bore out the TPS. I've got my TPS holes so bored out I'm afraid that it's gonna go on me someday, but that's ok because in my quest to fix my problem I bought a new one anyways. Oh wait, I mean my friend did.
Let us know how it works out for you.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Aug 14, 2005
#11
  • Aug 14, 2005
  • #11
[QUOTE='03GTinFLA]I know a guy, who know's a guy that crossed the two intake tubes when he was installing his Accufab 75mm TB and plenum. All kinds of idle problems. It would run about 1.5-2k and hang bad. He tried the copper pipe mod, then bored out both holes on his TPS, adjusted idle setting with his Predator and nothing fixed it. Then he just stopped and looked at his engine and realized his error. Now it runs great.
I would say first double check all your connections and make sure they are all on correctly. Then try the copper cap thing. If still nothing then bore out the TPS. I've got my TPS holes so bored out I'm afraid that it's gonna go on me someday, but that's ok because in my quest to fix my problem I bought a new one anyways. Oh wait, I mean my friend did.
Let us know how it works out for you. [/QUOTE]
Hey, I think I know that guy!
 
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