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start up issues

  • Thread starter Thread starter jimdrechsler
  • Start date Start date Oct 17, 2006

jimdrechsler

Member
Jun 29, 2006
248
1
18
Oct 17, 2006
#1
  • Oct 17, 2006
  • #1
its been cold here in ny, but this problem happens when it is warm as well. not as bad, but it still happens. when i start it up it needs gas after it starts to stay running. when i let up from the gas it almost stalls or will stall. i give it gas for about 30 seconds, just bringing the rpms up enough to keep it running. it stays running after that, but very low rpms for w while. it will eventually find the idle and idle fine. if i drive it when it is not at appropriate idle, it will pop at times through intake for a few minutes. when it gets up to operating temp, it runs fine with no popping. any ideas?

thanks for any replies
mods are in sig- timing i believe is set at 12. im not running the juice this year.
 
N

new46stang

Member
Jun 5, 2002
146
0
17
AZ
Oct 17, 2006
#2
  • Oct 17, 2006
  • #2
Have you pulled any codes yet? I would think you should start there.

Matt
 

jimdrechsler

Member
Jun 29, 2006
248
1
18
Oct 17, 2006
#3
  • Oct 17, 2006
  • #3
i have not, but may stop at autozone soon to have them do it. any guesses in the meantime?
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Oct 17, 2006
#4
  • Oct 17, 2006
  • #4
Yeah, autozone will probally try to sell you a O2 sensor. No really, is sounds like a slow Idle Air Controll (IAC). Either that or clogged. Try cleaning the TB and IAC first and see if it helps. Also, check for vacuum leaks.
 

jrichker

StangNet's favorite TOOL
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Oct 18, 2006
#5
  • Oct 18, 2006
  • #5
Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.



See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

Wal-Mart may now have the LCD display scanner for less than $35
 

LtDavis

20+ Year Stangneter
Nov 19, 2004
75
2
19
Raleigh, NC
Oct 18, 2006
#6
  • Oct 18, 2006
  • #6
I had the same problem, new O2 sensors cured the popping and jerking, and a new IAC valve cured the start up issue. I tried cleaning the IAC first but 120,000 miles worth of crud just wouldn't come off. The new IAC from Napa is shinny and better looking anyway!
 

jimdrechsler

Member
Jun 29, 2006
248
1
18
Oct 19, 2006
#7
  • Oct 19, 2006
  • #7
thanks for replies. not sure if this has anything to do with whats going on. but ive noticed that every once in a while when i start it, it will lose the memory for the radio and the cd pops out. battery seems fine though and no other cymptoms when after its started. stupid question---where is the iac exactly?
ps my car is a 90.
 

jrichker

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Oct 19, 2006
#8
  • Oct 19, 2006
  • #8
jimdrechsler said:
thanks for replies. not sure if this has anything to do with whats going on. but ive noticed that every once in a while when i start it, it will lose the memory for the radio and the cd pops out. battery seems fine though and no other cymptoms when after its started. stupid question---where is the iac exactly?
ps my car is a 90.
Click to expand...

Diagram courtesy of Tmoss & Stang&2birds


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif
 

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jimdrechsler

Member
Jun 29, 2006
248
1
18
Oct 21, 2006
#9
  • Oct 21, 2006
  • #9
Ok i just got back from autozone or advace auto- one fo those places. the guy there is a dope. he couldnt find where to plug in the handheld reader. i went about 5 years ago and it was under the hood when they did it. this guy was looking under the dash and couldnt find anything. he then proceeded to look behind the golve box. i found the EEC thing under the hood, but he said the pins wouldnt fit in there! where in the heck is this thing? AND, is his little dohickey able to read my 1990 car?

thanks- thoese guys that work at those places are idiots. he was telling me i had a turbo in the car too!!!
 

LtDavis

20+ Year Stangneter
Nov 19, 2004
75
2
19
Raleigh, NC
Oct 21, 2006
#10
  • Oct 21, 2006
  • #10
your 1990 has the OBDI diagnostic port, its under hood right near the firewall on the driver's side. Its just a plug dangling from a piece of wiring harness. The idiot at the parts store was probably thinking of OBDII which is usually under the drivers side dash.
 

jimdrechsler

Member
Jun 29, 2006
248
1
18
Oct 21, 2006
#11
  • Oct 21, 2006
  • #11
i knew it was under the hood. what a loser. i dont think they have the one then. they are fn idiots there!! act like they no it all!
 
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