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

blackish smoke and rough idle'ing.

  • Thread starter Thread starter mcginnt
  • Start date Start date Jun 13, 2006
M

mcginnt

New Member
Feb 17, 2006
7
0
0
Jun 13, 2006
#1
  • Jun 13, 2006
  • #1
ok, let me explain how this all came about.

im running a 1998 5.0 mustang gt convert. it had some electral problems when i first got it and have since fixed most of it.
one day i was driving to work and went around a turn and it cut out. fuel pump wouldnt turn on. towed it to my house, looked thru everything.

this is what i then went on to fix... i dropped the tank and checked the fuel pump and it worked strong. long story short, wires were all correct but the computer was not sending anything to it.

i replaced the computer with a new one and found a short in a fuseable link from the starter celonid and now the pump works fine.

i put new spark plugs, plug wires, distributer cap, oil filter, fuel filter. and everything i replaced.

i tried adjusting the idle but regardless where i put it it idles around 800-1000 but varies. its louder now and it sounds like its mis-fireing but i dont know.

its not white, blue, or gray smoke. its black, it doesnt fill the sky but its black when it comes out.


please any ideas about what this could be?
:damnit:
(ps. i tried to use the plug to get any error codes but its not working for some reason)
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jun 13, 2006
#2
  • Jun 13, 2006
  • #2
black smoke means you are running rich. Try cleaning your iac.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jun 13, 2006
#3
  • Jun 13, 2006
  • #3
You have a 98 GT with a 5.0?

What computer are you running?

Can you create a sig with some of your modifications, so we all know more about your car?

jason
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jun 14, 2006
#4
  • Jun 14, 2006
  • #4
If that was a typo and is an '88 like Jason said, pull codes. Run a cylinder balance test to look for your miss and look for MAP codes. Especially if still SD, check the MAP sensor and look for vac leaks. A stockish SD motor should knock down near 20" of vac at idle. If less than that, the puter gets hinky (the vac signal is critical).

Good luck.
 
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