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

rpm's dropping too quickly

  • Thread starter Thread starter SaleenGT2001
  • Start date Start date May 10, 2006

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
May 10, 2006
#1
  • May 10, 2006
  • #1
ever since i took off my 70mm tb for the new 75mm one, my car will cut off if you pull it out of gear from higher rpms. 3000 and up. even with the s/c it still does. i thought the tb was just too big for a N/A engine but with the s/c i cant figure out why it cuts off. almost everytime i go into neutral it will drop VERY quickly to around 600 rpm sometimes it will recover to idle at 1000rpm and sometimes it just dies. did i do something wrong when i put the TB on? should i just run the idle screw out farther?
 

Mossberg

Active Member
Jul 21, 2003
0
1
36
ATL, Shawty
May 10, 2006
#2
  • May 10, 2006
  • #2
Adjust the TPS screw and you should be OK.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
May 10, 2006
#3
  • May 10, 2006
  • #3
what rpm should i adjust the idle to?
 

Mossberg

Active Member
Jul 21, 2003
0
1
36
ATL, Shawty
May 10, 2006
#4
  • May 10, 2006
  • #4
Mine is at an 800 rpm idle. Check your voltage.
 
C

ceracer33

New Member
Aug 30, 2005
118
1
0
May 10, 2006
#5
  • May 10, 2006
  • #5
sounds to me like ur iac valve. it might not be bad, but it sounds like its not getting adequate airflow. i would check the vacuum line going to it and make sure its not plugged up or anything, but it sounds to me like a faulty iac valve.

edit: u could also try removing the iac valve and cleaning it. im not sure but i think on the 01's they have an internal iac, which means it doesnt have a vacuum line going to it. i just thought about that. but it definately sounds like an iac problem.
 

four six

Member
Jan 19, 2006
506
2
18
Hobart, IN
May 11, 2006
#6
  • May 11, 2006
  • #6
ceracer33 said:
sounds to me like ur iac valve. it might not be bad, but it sounds like its not getting adequate airflow. i would check the vacuum line going to it and make sure its not plugged up or anything, but it sounds to me like a faulty iac valve.

edit: u could also try removing the iac valve and cleaning it. im not sure but i think on the 01's they have an internal iac, which means it doesnt have a vacuum line going to it. i just thought about that. but it definately sounds like an iac problem.
Click to expand...

+1 for this
 

four six

Member
Jan 19, 2006
506
2
18
Hobart, IN
May 11, 2006
#7
  • May 11, 2006
  • #7
did the kit come with a tune?
If so could the changing of the TB throw it off
 
M

mac1009

Founding Member
Feb 17, 2001
187
0
0
Atlanta, GA
May 11, 2006
#8
  • May 11, 2006
  • #8
Let Tim know it's happening and he'll fix it in your tune.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
May 11, 2006
#9
  • May 11, 2006
  • #9
it didnt do it but once today. and that was when it was cold. maybe the computer was just learning everything.
 
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