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

Plenum and Throttle Body Help!

  • Thread starter Thread starter BrK02Gt
  • Start date Start date Jul 21, 2005
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BrK02Gt

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Jul 21, 2005
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Jul 21, 2005
#1
  • Jul 21, 2005
  • #1
I just installed a Mac 75MM Throttle Body and Upper Intake Plenum and can not get the car to idle properly. I've heard about setting the TPS voltage to .99 but it still seems to hold idle. Is there anything else that could be causing it to hold idle if the TPS is dialed in?
 

97StallionGT

Member
Apr 6, 2005
113
0
16
Easley, SC
Jul 21, 2005
#2
  • Jul 21, 2005
  • #2
I had the same problem when I installed mine. RPM's hang badly too. Havent found a way to fix it yet...hopefully someone on here will know
 

forpit2000gt

Founding Member
Jun 30, 2002
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Columbia, SC
Jul 21, 2005
#3
  • Jul 21, 2005
  • #3
Mine did this on a 2000. I removed the positive battery terminal for about 10 minutes, then replaced. I had to drive the car for a few miles then it was fine. BTW, I also had a leak around the plenum that caused some problems at first. I removed and retightened.
 
R

Rocketman

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Apr 20, 2004
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SoCal
Jul 21, 2005
#4
  • Jul 21, 2005
  • #4
Prior to the install did you disconect the battery so that the computer would reset?

Also, it took my car a few days to settle in when I put on my Accufab.
 
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BrK02Gt

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Jul 21, 2005
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Jul 21, 2005
#5
  • Jul 21, 2005
  • #5
Yea I disconnected the negative for an hour but I didn't disconnect the positive. I thought you only had to disconnect the neg. for 30 minutes to reset the computer. Everything seemed sealed correctly with no air leaks. Also when i put the stock stuff back on it had no problems. This would signify that all my sensors are working properly. Do most people have to mess with the TPS when doing the swap?? Thanks for the help
 

97StallionGT

Member
Apr 6, 2005
113
0
16
Easley, SC
Jul 21, 2005
#6
  • Jul 21, 2005
  • #6
I'll try the battery thing today
 

BooWFO

New Member
May 10, 2005
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Louisville, KY
Jul 21, 2005
#7
  • Jul 21, 2005
  • #7
Over on MAC's website there are few ? about the TB on there some mention the gasket is too thick some same the return spring brakcet needs to be twisted....
I put one on mine messed with it til I had tps set perfect just to have something similiar happen (blade was catching on inside of plenum ) I just yanked it off went back to stock. I gteched it not any difference over stock and I don't need to pull plenum and port it more.
 
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BrK02Gt

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Jul 21, 2005
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Jul 21, 2005
#8
  • Jul 21, 2005
  • #8
Has anyone ever had a Mac plenum and throttle body work?
 

forpit2000gt

Founding Member
Jun 30, 2002
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Columbia, SC
Jul 21, 2005
#9
  • Jul 21, 2005
  • #9
I just read again and realized that ist is MAC. I have C&L. Maybe call MAc and seee what they say. Does the MAC TB have an adjustment screw. Make sure all connections behind the MAF are good and tight.
About the battery. I said 10 min., I never really waited that lon. Usually 5. I have heard both , neg or pos. not really sure now that it makes a difference. I mash the brake pedal before reconnecting. Wire holds a small amount of power anyways. This is what worked for me .
 
A

AtlanticGT

New Member
Dec 23, 2004
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0
Jul 21, 2005
#10
  • Jul 21, 2005
  • #10
This may sound like a stupid question, but did you install the spring when you put it back on? I forgot mine and couldn't figure out why the idle wasn't coming down until I found the spring in my pocket
 
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BrK02Gt

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Jul 21, 2005
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Jul 21, 2005
#11
  • Jul 21, 2005
  • #11
Yea the spring and everything else is on. I might just let my speed shop that sold it to me mess with it, they said they'd put them both on for $75 so that way if they can't fix it i can just get my money back
 

jrc_03_gt

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Jan 1, 2004
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Jul 21, 2005
#12
  • Jul 21, 2005
  • #12
My egr was not sealed up good. You need to make sure it is tight. Use gasket that came with plenum. I tried to use the stock one and it did not seal. That fixed my hanging rpm's .
 
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BrK02Gt

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Jul 21, 2005
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#13
  • Jul 21, 2005
  • #13
That could be my problem, is it necessay to have the EGR on there extremely tight?
 

OUR01GT

New Member
Mar 31, 2005
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EAST CENTRAL OHIO
Jul 21, 2005
#14
  • Jul 21, 2005
  • #14
The EGR needs to be torqued down VERY tight! I f you don't have a manual to get the torque specs call your FORD dealer. Good luck!
 

OUR01GT

New Member
Mar 31, 2005
121
0
0
EAST CENTRAL OHIO
Jul 22, 2005
#15
  • Jul 22, 2005
  • #15
Here are the torque specs for anyone who is planning on doing a swap like this:

UPPER INTAKE PLENUM - TORQUE BOLTS TO 7 ft./lbs.

EGR - TORQUE BOLTS TO 18 ft./lbs.

THROTTLE BODY - TORQUE BOLTS TO 7 ft./lbs.

1 in./lb. = .083 ft./lbs.

 
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