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

car dies right after start

  • Thread starter Thread starter jmd2914
  • Start date Start date Aug 28, 2006
J

jmd2914

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Napa, California
Aug 28, 2006
#1
  • Aug 28, 2006
  • #1
when i start the car it starts but dies immediately. what could be causing this???
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
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Senoia, GA
Aug 28, 2006
#2
  • Aug 28, 2006
  • #2
IAC could be totaly dead. That happened to me once.
 

HISSIN50

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15 Year Member
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#3
  • Aug 28, 2006
  • #3
It can also be a bad TFI/TFI wiring if you have a grey TFI module.

Any other symptoms? Does it eventually start and stay running?

Good luck.
 
J

jmd2914

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Aug 29, 2006
#4
  • Aug 29, 2006
  • #4
yeah usually it will die once then start right up afterwards. i replaced the tfi mod about a year ago do they go bad that quickly?
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
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Aug 29, 2006
#5
  • Aug 29, 2006
  • #5
When a TFI goes bad normally it wont start at all.
 
J

jmd2914

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Aug 29, 2006
#6
  • Aug 29, 2006
  • #6
hmm so what would make it only die once then start again?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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#7
  • Aug 29, 2006
  • #7
If it starts up after its initial burp, it's likely not the TFI then.

On the grey ones, there's a terminal that differentiates starting vs running - that's the angle I was taking before.

In your case, what happens if you prime the pump a couple of times (cycle the key on and off, pausing for 5 seconds when turned on) before ever trying to start it?
If this helps, that indicates a fuel pressure issue, which is often a weak check valve in the pump assembly.

Good luck.
 
J

jmd2914

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Aug 29, 2006
#8
  • Aug 29, 2006
  • #8
how do i remedy this? just replace the fuel pump?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 29, 2006
#9
  • Aug 29, 2006
  • #9
DId cycling the key make it start and stay running?

A weak check valve doesnt mean a whole lot necessarily. A lot of us have a weak valve but the pump keeps running well for a long time.
 

xhatchetboyx

New Member
Jun 27, 2006
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Aug 29, 2006
#10
  • Aug 29, 2006
  • #10
lol uh might be your aulternater and a dead batterie? that happend to me not to long ago....
 

Mavrick

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Aug 29, 2006
#11
  • Aug 29, 2006
  • #11
Sounds like an IAC to me. Remove your IAC and clean it with carb cleaner..
 

Georgie

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Jul 13, 2005
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Aug 29, 2006
#12
  • Aug 29, 2006
  • #12
humm..try the inartia switch in the trunk...has to be pushed DOWN for ON and pulled UP for OFF
 
J

jmd2914

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Aug 29, 2006
#13
  • Aug 29, 2006
  • #13
hmm didnt even know i had an inertia switch in my trunk. when i let the pump prime it started right up
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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Aug 30, 2006
#14
  • Aug 30, 2006
  • #14
If your pump primes, your inertia switch is fine.

It sounds like a bad check valve at the pump.
 
J

jmd2914

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Aug 30, 2006
#15
  • Aug 30, 2006
  • #15
so is this something i need to worry about?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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Aug 30, 2006
#16
  • Aug 30, 2006
  • #16
Unless it's bothersome, I personally would not sweat it so long as the pump continues to function and keep pressure. The check valve really has nothing to do with the diaphram and motor assembly - there have been new pumps installed that did the same darn thing (it's kinda prevalent on 94-95's for some stupid reason - they use the same pumps we do).

I will say that normally with a pump like that, if you dont cycle the key, normally you'd have to crank for a few seconds but once it caught (started), it would stay running. It's strange that it catches, dies and restarts immediately.

Random thoughts way too late at night. Good luck.
 

jrichker

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Aug 30, 2006
#17
  • Aug 30, 2006
  • #17
The startup & immediately die, restart and it runs, is a IAB problem. Mine's doing it now along with some of the other IAB problems that are common to 5.0's. For cures, see the Surging Idle tech note in the "Useful Technical Thread Index" sticky at the top of the forum.
 

Georgie

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#18
  • Aug 30, 2006
  • #18
or just buy a book like jrichker says
 
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