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

Won't stay running

  • Thread starter Thread starter Ryon Oud
  • Start date Start date Jan 22, 2013

Ryon Oud

New Member
Jan 20, 2013
4
0
1
Jan 22, 2013
#1
  • Jan 22, 2013
  • #1
I fixed the fuel problem, now it starts up reves up pass 3000 RPM's the as it idles down it shuts off or stalls. but it you put your foot on the gas and keep it up pass 1000 RPM's it will run.
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Jan 22, 2013
#2
  • Jan 22, 2013
  • #2
vacuum leak?
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,813
234
Dublin GA
Jan 22, 2013
#3
  • Jan 22, 2013
  • #3
See the "Surging Idle Checklist” for help with all your idle/stall problems. You can guess at the problem and throw parts at it, or you can use the checklist to help you find the problem quickly and inexpensively. The checklist is right here in the Stangnet 5.0 Tech forum and you don’t have navigate to some other unknown web site. It‘s free and doesn’t cost anything: at last count there were more than 103,000 visits and still climbing

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 

madspeed

Colonel Mustard
Founding Member
Nov 29, 1999
8,914
1,332
204
a van down by the river
Jan 22, 2013
#4
  • Jan 22, 2013
  • #4
iac and idle screw. See Jrichters list. follow it to a t and it will fix your issue
 
J

jka

5 Year Member
Jan 17, 2010
339
23
29
Jan 22, 2013
#5
  • Jan 22, 2013
  • #5
Adjust the idle to what idle speed you like or 750-800 and let your engine warm up ..then disconnect both battery cables for 30 min then reconnect both cables. Then start the engine and let it idle then drive around for about 20 min then turn your car off for a few mins then start it again. Check your idle speed..by then with a warm engine it should be at about 800-850. The real test will be on cold start up..but doing this should help idle and the stalling.
 

Bill Gordon

Active Member
Sep 20, 2012
119
12
29
Broomfield, CO
Jan 22, 2013
#6
  • Jan 22, 2013
  • #6
I would follow jrichkers advice, there is a wealth of information in the links he posts.
 
J

jka

5 Year Member
Jan 17, 2010
339
23
29
Jan 23, 2013
#7
  • Jan 23, 2013
  • #7
He can follow anybody info he likes..i know what works for me..some stuff can't be learn in a book or on a site..some stuff comes from doing. It has worked for me for 15 years as a ford tech and plus i have own a few mustangs ..and not to say i'm perfect..but i was just giving my advice. If i joined this site to help people why wouldn't i give my own advice. Not to say i'm right and not to say nobody wrong..everybody just has different ways of doing stuff.
Bill Gordon said:
I would follow jrichkers advice, there is a wealth of information in the links he posts.
Click to expand...
 

JordanB21

Active Member
Feb 6, 2012
804
27
29
Killeen, Texas
Jan 23, 2013
#8
  • Jan 23, 2013
  • #8
jka said:
He can follow anybody info he likes..i know what works for me..some stuff can't be learn in a book or on a site..some stuff comes from doing. It has worked for me for 15 years as a ford tech and plus i have own a few mustangs ..and not to say i'm perfect..but i was just giving my advice. If i joined this site to help people why wouldn't i give my own advice. Not to say i'm right and not to say nobody wrong..everybody just has different ways of doing stuff.
Click to expand...
Nobody is discrediting you, all knowledge is welcome!

jricher is just the typical guy to listen to. Though I often see people join the site, post once asking for help, and jricher will give them a check list and then you never hear from them again.
Probably look at it and decide they rather take it to a shop.
 
J

jka

5 Year Member
Jan 17, 2010
339
23
29
Jan 23, 2013
#9
  • Jan 23, 2013
  • #9
Okay it's cool.
 
Reactions: JordanB21

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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Dublin GA
Jan 23, 2013
#10
  • Jan 23, 2013
  • #10
JordanB21 said:
Nobody is discrediting you, all knowledge is welcome!

jrichker is just the typical guy to listen to. Though I often see people join the site, post once asking for help, and jrichker will give them a check list and then you never hear from them again.
Probably look at it and decide they rather take it to a shop.
Click to expand...
Thanks for the vote of confidence.

They either fix the problem very quickly or get scared off... I use a checklist procedure because there are so many variables and things not said that it is very often difficult to tell what's going on. Overall, it saves time, sweat and skin, even if it is a little intimidating at first.

FYI, I have been DIY fixing cars for 49 years and the last 20 of that has been with 5.0 fox body EFI Mustangs. Stangnet has greatly contributed to my knowledge of auto repair because it makes me stop and think about how it really does work. I get to help fix things I'd never see in real life - too busy with my real job, fixing computers.
 
Reactions: JordanB21 and madspeed

Bill Gordon

Active Member
Sep 20, 2012
119
12
29
Broomfield, CO
Jan 23, 2013
#11
  • Jan 23, 2013
  • #11
jka said:
He can follow anybody info he likes..i know what works for me..some stuff can't be learn in a book or on a site..some stuff comes from doing. It has worked for me for 15 years as a ford tech and plus i have own a few mustangs ..and not to say i'm perfect..but i was just giving my advice. If i joined this site to help people why wouldn't i give my own advice. Not to say i'm right and not to say nobody wrong..everybody just has different ways of doing stuff.
Click to expand...
I'm not discrediting anybody's input, I think that everyone agrees that all input is welcome. The more info the better.
All I was trying to say is that jrichker obviously spends a great deal of time putting this info up here and it is very detailed and informative. I welcome all advice when I run into a problem.
 

JordanB21

Active Member
Feb 6, 2012
804
27
29
Killeen, Texas
Jan 23, 2013
#12
  • Jan 23, 2013
  • #12
jrichker said:
Thanks for the vote of confidence.

They either fix the problem very quickly or get scared off... I use a checklist procedure because there are so many variables and things not said that it is very often difficult to tell what's going on. Overall, it saves time, sweat and skin, even if it is a little intimidating at first.

FYI, I have been DIY fixing cars for 49 years and the last 20 of that has been with 5.0 fox body EFI Mustangs. Stangnet has greatly contributed to my knowledge of auto repair because it makes me stop and think about how it really does work. I get to help fix things I'd never see in real life - too busy with my real job, fixing computers.
Click to expand...
Anytime!
 

zacks89

New Member
Jan 23, 2013
9
0
1
Jan 24, 2013
#13
  • Jan 24, 2013
  • #13
Yea i had the same prob not to long ago bro. Thats all good advice. I replaced my iac and adjusted my tps and that really helped my fox.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jan 24, 2013
#14
  • Jan 24, 2013
  • #14
jka said:
Adjust the idle to what idle speed you like or 750-800 and let your engine warm up ..then disconnect both battery cables for 30 min then reconnect both cables. Then start the engine and let it idle then drive around for about 20 min then turn your car off for a few mins then start it again. Check your idle speed..by then with a warm engine it should be at about 800-850. The real test will be on cold start up..but doing this should help idle and the stalling.
Click to expand...

So what if it fails the cold start up stall test until it gets warmed up? Then what?
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jan 24, 2013
#15
  • Jan 24, 2013
  • #15
jrichker said:
Thanks for the vote of confidence.

They either fix the problem very quickly or get scared off... I use a checklist procedure because there are so many variables and things not said that it is very often difficult to tell what's going on. Overall, it saves time, sweat and skin, even if it is a little intimidating at first.

FYI, I have been DIY fixing cars for 49 years and the last 20 of that has been with 5.0 fox body EFI Mustangs. Stangnet has greatly contributed to my knowledge of auto repair because it makes me stop and think about how it really does work. I get to help fix things I'd never see in real life - too busy with my real job, fixing computers.
Click to expand...

You need to add a list of the magic swear words to complete the check lists. otherwise you are extremely helpful!
 
J

jka

5 Year Member
Jan 17, 2010
339
23
29
Jan 24, 2013
#16
  • Jan 24, 2013
  • #16
After this it shouldn't stall on cold start and it should idle better in open loop.. if steps are done right ..and also by pulling both battery cables it will force computer reset/learn the stuff you have changed. Most people pull just the neg cable..but that's fine for short term memory ..but if you have adjusted everything ..it's better to force it to relearn everything. If none of this stuff works it may be a fuel problem/running lean on cold start ..maybe a bad ECT/ACT sensor or mass air sensor or even a weak fuel pump. This does not work on every mustang.. it depends on what his problem really is ..but it has work on every mustang that i worked on that was stalling on cold start and was suring.
7991LXnSHO said:
So what if it fails the cold start up stall test until it gets warmed up? Then what?
Click to expand...
 
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