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why does it die at idle after i get on it?

  • Thread starter Thread starter zeusmoto
  • Start date Start date Jul 11, 2004
Z

zeusmoto

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Feb 15, 2004
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Jul 11, 2004
#1
  • Jul 11, 2004
  • #1
just like the wuestion says, i will race or go on the freeway then when i come to a stop my tach goes a little crazy and the car dies, i have an auto, any ideas of what it could be? i would like to fix this problem.... it really sucks..please help
 

ECU5.0

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Jul 11, 2004
#2
  • Jul 11, 2004
  • #2
could be your tps voltage is way off
 

HISSIN50

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Jul 11, 2004
#3
  • Jul 11, 2004
  • #3
there is also some sort of speed sensor that is supposed to keep the revs up (around 1500) when you let off the gas, so the car does not die. IAC can also do it.
 
Z

zeusmoto

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#4
  • Jul 11, 2004
  • #4
how do both of you guru's suppose i go about this to fix it? sometimes at idle even driving normally, the rpms arent always even, sometimes but not always... is it an easy fix?
 
Z

zeusmoto

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#5
  • Jul 12, 2004
  • #5
anybody?
 

r6bullet

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#6
  • Jul 12, 2004
  • #6
I would take your IAC off and give it a real good cleaning, make sure you don't press on the part the moves inside of their, I think it is called the pintle. You could mess it up if you push on that, just make sure that is clean. And double check your tps voltage. At idle or 0% throttle it should be around .96 volts
 
Z

zeusmoto

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#7
  • Jul 12, 2004
  • #7
how do you check it?
 

jrichker

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#8
  • Jul 12, 2004
  • #8
Here’s a TPS tip I got from NoGo50…

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .80v-.99v, Just don’t go over .99, or you’ll upset the fuel calibration and idle quality may suffer, along with some other problems like poor gas mileage.


(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Drive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground. Use Green & Black wires for your measurements.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .80v-.98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .80v-.98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.
 
Z

zeusmoto

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#9
  • Jul 12, 2004
  • #9
what would cause it to die sometimes but not die others?
 

beaver2489

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st. joseph missouri
Jul 12, 2004
#10
  • Jul 12, 2004
  • #10
I had that problem with my '89 auto...I'd drive it 50miles out of town to Kansas City and it would die as soon as I'd get off the interstate. I replaced the TPS sensor and set it at .98v, cleaned my IAC, replaced the TFI module...and it still died when I drove it reallll hard or on the interstate. I replaced my distributor and it went away. I found on here that there is a PIP (I think its called) sensor in the distributor that when it overheats the signal to send spark shuts off or something like that. When mine would die, I would have to leave it sit for 40min before it would start back up. Also the next time your car dies, open the hood and wiggle the TFI module wire connector. I had a buddy have the same problem and his TFI wire harness would come loose. good luck
 
Z

zeusmoto

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Jul 13, 2004
#11
  • Jul 13, 2004
  • #11
thanks but where is this tfi? that may be the case but my car starts up again automatically, i have a new distributor cap rotor.. etc so i dont know though so any more help would be appreciated
 

HISSIN50

"How long does it take to get help in here?
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#12
  • Jul 13, 2004
  • #12
TFI is the plastic connector on the side of the dizzy. PIP is on the dizzy shaft (you have to pull the dizzy to get to it).
 
Q

Quick5pnt0

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#13
  • Jul 13, 2004
  • #13
I'm not sure how much it will help, but you can try this...
http://www.muscularmustangs.com/iac.html
 
B

barthy00GT

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Jul 2, 2004
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Jul 13, 2004
#14
  • Jul 13, 2004
  • #14
Not too sure if this will help ya out, but my 2000 mustang was doing the same thing. There are all sorts of recalls on them quitting and as far as i've seen it's always with the intake system. So instead of taking it in and getting new factory crap on it i just went ahead and bought a cool air intake and a throttle body. Sence then the car has idled down on me once or twice to about 200rpm but has cought it's self every time.

BBK cool air intake
BBK 75mm throtle body
BBK full length headers
BBK shorty X-pipe no cats
Flowmaster thunder series cat back
BBK underdrive pullies
hurst short throw
chrome valve covers
aluminum drive line
1.5 drop
18' 03 cobra rims
cobra R spoiler
Steeda racing chin splinter
2' Steeda fiberglass hood
black with Blue pearl flames (airburshed)
 
Z

zeusmoto

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#15
  • Jul 13, 2004
  • #15
yeah almost my whole car is aftermarket already, so that didnt solve the problem. but how do i mess with the iac it has two screws doesnt it and do i just loosen both of them or what? and to clean it what do i do?
 
Z

zeusmoto

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Feb 15, 2004
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Jul 13, 2004
#16
  • Jul 13, 2004
  • #16
please help
 
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