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

running lean..

  • Thread starter Thread starter 19stang87
  • Start date Start date Apr 28, 2004

19stang87

New Member
Apr 29, 2003
134
0
0
WoodStock,GA
Apr 28, 2004
#1
  • Apr 28, 2004
  • #1
ok i pulled a plug for the hell of it lastnite and its all white...soo how would i fix that on a SD motor juss bumping the fuel pressure or is there any other ways....i dont have FPR well a adjustable one that i know..so do i need one b4 i ask this?

thanxs
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Apr 28, 2004
#2
  • Apr 28, 2004
  • #2
My car is running lean and it is throwing codes 41 and 91 for the O2 sensors. I need to change them to see if it helps. Does yours have any codes?
 

91LX302

Founding Member
Jun 22, 2002
248
0
16
Boston, MA
Apr 28, 2004
#3
  • Apr 28, 2004
  • #3
If you want to tune your fuel pressure you need an adj. FPR. Check for some codes, that's the first thing I would do. I've also received codes 41 and 91. I think it's my fuel pump, I lose pressure past 3k rpm in 3rd gear and up. Hopefully that solves my problem.
 

19stang87

New Member
Apr 29, 2003
134
0
0
WoodStock,GA
Apr 29, 2004
#4
  • Apr 29, 2004
  • #4
well i would do the code test but no one around here has a scanner for older cars all new crap....so if anyone knows where in NW ga i can go lemme know......how much is a scanner for my car a 87
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Apr 29, 2004
#5
  • Apr 29, 2004
  • #5
Jeez, you dont need a code scanner to read your codes. All you need is an analog voltmeter and a piece of wire. Even the rotten Haynes/Chiltons manuals tell you how to do it. Its really easy and you can use the voltmeter for other things. And yes, you need an adustable fuel pressure regulator before you can.......adjust the fuel pressure. You also need a gauge so you can tell where your pressure is at.
 

bighoss88lx

Founding Member
Sep 6, 2002
537
0
0
San Antonio, Texas
Apr 29, 2004
#6
  • Apr 29, 2004
  • #6
My SD is doing the same. Subscribing.
 

91LX302

Founding Member
Jun 22, 2002
248
0
16
Boston, MA
Apr 29, 2004
#7
  • Apr 29, 2004
  • #7
http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

that should help
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Apr 29, 2004
#8
  • Apr 29, 2004
  • #8
Good info 91LX302. But I always use a test light instead of the voltmeter. It is much easier to see and read especially while inside the car.
 
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