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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Engine The Car Up To 4000 Rpm

  • Thread starter Thread starter Luis911
  • Start date Start date Jun 23, 2013

Luis911

Member
Nov 9, 2005
114
0
17
Mexico City
Jun 23, 2013
#1
  • Jun 23, 2013
  • #1
to start the car, speeds up to 4000 rpm and I turn it off, I turn it on and running normally, that is failing? in the last two weeks this has happened 3 times (Friday failed many times and I could not start the car normally, Saturday and today it worked normal, but I think it will return to fail).
KOEO 34
KOER 12, 21
 

Luis911

Member
Nov 9, 2005
114
0
17
Mexico City
Jun 25, 2013
#2
  • Jun 25, 2013
  • #2
returned to fail, in the iac valve throttle is the whip, but when starting the car the whip moves back as if he stepped on the gas pedal.

perhaps be the iac valve is stuck?
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
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69
New Bedford, MA
Jun 25, 2013
#3
  • Jun 25, 2013
  • #3
So you're saying the idle revs up on its own? That would be the TPS (throttle position sensor)
 

Luis911

Member
Nov 9, 2005
114
0
17
Mexico City
Jun 25, 2013
#4
  • Jun 25, 2013
  • #4
if the tps sensor is damaged, this can cause the car to accelerate too?
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
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In the garage
Jun 25, 2013
#5
  • Jun 25, 2013
  • #5
Luis, run the surging idle checklist by jrichker. It will answer your questions.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
Jun 25, 2013
#6
  • Jun 25, 2013
  • #6
Luis911 said:
if the tps sensor is damaged, this can cause the car to accelerate too?
Click to expand...


If it holds that high idle and wont go down unless you turn the car off....then yes. This wouldn't be surging (up and down idling) In the good old days i delivered pizza in a car with a built HCI 306.....I would be at a redlight and the idle would climb high enough for me to do a burnout....lol
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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Dublin GA
Jun 25, 2013
#7
  • Jun 25, 2013
  • #7
You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix. :

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 125,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 

Luis911

Member
Nov 9, 2005
114
0
17
Mexico City
Jun 27, 2013
#8
  • Jun 27, 2013
  • #8
I was checking "surging idle checklist", but I think my problem is related to "speed control".
When I start the car, the accelerator pedal and whip move alone, so the rpm rise quickly and I have to turn off the car, removed fuse number 6 of 20 amps, the label says "speed control" and other things, and the start the car has worked well, I do not know if you solved the problem or will fail again.
I guess some of the "speed control" damage, and this causes it to move the gas pedal, I was seeing that there are 2 whips that reach the throttle body, and one goes to the pedal and the other to any control system speed.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,945
224
Massachusetts
Jun 27, 2013
#9
  • Jun 27, 2013
  • #9
Disconnect the cruise control cable and see if the problem stops
 

Luis911

Member
Nov 9, 2005
114
0
17
Mexico City
Jun 27, 2013
#10
  • Jun 27, 2013
  • #10
Mustang5L5 said:
Disconnect the cruise control cable and see if the problem stops
Click to expand...
During the day I used the car and has not failed, I have on and off several times and all good, probably the fuse that was removed disabled the "speed control" and / or "cruise control" and how to disconnect the cruise control cable? thanks
 
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