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

new TB/Plenum question?

  • Thread starter Thread starter DUKE
  • Start date Start date Sep 11, 2004
D

DUKE

Founding Member
Jan 27, 2002
52
0
0
Hampton, Va
Sep 11, 2004
#1
  • Sep 11, 2004
  • #1
I installed a new Accufab TB and plenum. The idle starts to climb to around 3k and I took off the IAC connection while I was under the hood and the idle came back down to around 700 and stayed there. Does this mean I have a bad IAC valve and need to get a new one? Also, if my idle is back to wher it was befoer the install of the new parts, do I still need to check the volts of the TPS with a volt meter?

Thank you for any help-
 

lightblade

Member
Aug 7, 2004
366
0
17
Sep 11, 2004
#2
  • Sep 11, 2004
  • #2
i have the the accufab 75mm tb nad plenum too, if your car idels with the iac off and mess up plugged in then it needs replaced, but furst u could try and clean it with some carb cleaner first if it still wont idle then it needs rplaced, dont mess with the tps
 
J

JimC

Member
Dec 1, 2002
170
0
17
Duluth GA
Sep 11, 2004
#3
  • Sep 11, 2004
  • #3
Not necessarily a bad iac but the voltage may need to be set. I would start there first.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Sep 11, 2004
#4
  • Sep 11, 2004
  • #4
JimC said:
Not necessarily a bad iac but the voltage may need to be set. I would start there first.
Click to expand...
Voltage? You must be talking about the TPS.
I had no issue with this mod...no messing around with a voltmeter on the TPS. Heck, even Accufab said you can just manually adjust, if necessary - they said that's what they actually do themselves.
But, Duke, this sounds like a bad IAC.
Did you reset the computer when you swapped the plenum and TB out?
 
D

DUKE

Founding Member
Jan 27, 2002
52
0
0
Hampton, Va
Sep 12, 2004
#5
  • Sep 12, 2004
  • #5
Thanks for the replies. Yes, I had the battery disconnected for about an hour. I hookde my volt meter to the TPS and even removed the two bolts holding it down and I couldn't get a higher reading on volts than a 0.02??
I think I could have a bad TPS and needs replaced?
 

StangLou

Active Member
Jul 9, 2003
1,264
0
36
Holly Springs, NC
Sep 12, 2004
#6
  • Sep 12, 2004
  • #6
Its more than likely NOT your TPS. You normally wont notice anything at idle with a bad tps. You will however notice that the throttle responce going out with a bad tps. You may floor the car and it will just sit there, and stuff like that. A bad idle is usually a sign of a bad iac.
After many people did this swap they all seemed to have a "sticking" idle. I did as well. After the install, I started the car up and it fired up fine, then when the revs started to come down it stuck at 1200-1300rpms for about 4-5 seconds then would drop back down to normal. This is apparently normal with this mod. It will wear off after a week or so of driving.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Sep 12, 2004
#7
  • Sep 12, 2004
  • #7
Yep, as Lou experienced, mine noticably calmed down 5 days after the install...behaves like stock now.
 
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