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

im lost

  • Thread starter Thread starter nicks87
  • Start date Start date May 12, 2010
N

nicks87

New Member
May 12, 2010
2
0
0
elyria,ohio
May 12, 2010
#1
  • May 12, 2010
  • #1
hello im new to the site.i have always loved mustangs how ever i have alway worked on classics. recently i bout a 87 lx 5.0 this past winter i did a b303 cam swap mass air conversion smog pump delete and pulleys.i start the car it runs good no miss, timeing is dead on,but after a few it slowly loads up i tried turning timeing back looked over all my work about a million times i dont have a computer to cheak for codes so i was wondering if any one could give me some advice or a direction to go thanks nick
 

tb9050lx

Member
Mar 7, 2004
155
3
19
ct
May 12, 2010
#2
  • May 12, 2010
  • #2
nicks87 said:
hello im new to the site.i have always loved mustangs how ever i have alway worked on classics. recently i bout a 87 lx 5.0 this past winter i did a b303 cam swap mass air conversion smog pump delete and pulleys.i start the car it runs good no miss, timeing is dead on,but after a few it slowly loads up i tried turning timeing back looked over all my work about a million times i dont have a computer to cheak for codes so i was wondering if any one could give me some advice or a direction to go thanks nick
Click to expand...

what do you mean it loads up ?
 
N

nicks87

New Member
May 12, 2010
2
0
0
elyria,ohio
May 12, 2010
#3
  • May 12, 2010
  • #3
plugs turn black acts like it is flooding out getting to much gas from some were but b4 i parked it last fall it was all stock and ran good
 
S

srjs28

New Member
Jan 12, 2010
69
0
0
May 12, 2010
#4
  • May 12, 2010
  • #4
maf conversion? did you upgrade your mass air meter? if so is it calibrated with your injectors. just a thought
 

Beasty306GT

Active Member
Dec 19, 2002
671
4
28
Oxford,Mass
May 12, 2010
#5
  • May 12, 2010
  • #5
u probably need a fuel pressure regualtor
 
V

v8only

Active Member
Jul 3, 2003
2,378
22
49
May 12, 2010
#6
  • May 12, 2010
  • #6
fuel pressure regulators are damned near useless....the computer compensates for changes made with the fuel pressure regulator.

The 87s came with speed density, not mass air.

A speed density system relies on a steady high vacuum signal to the map sensor on the firewall. The computer uses the vacuum signal essentially to know how far you have your foot buried into the gas.

See, a stock cammed 5.0 will put out on average 17-20 pounds of vacuum at idle. I've got the same b303 cam that you have, and I put out around 11 pounds at idle.

The stupid speed density computer is looking at the 11 pounds of vacuum that your engine is making at idle, so it's thinking you have your foot buried in the gas, and the computer is screaming, more fuel, more fuel!!!!

do a search on mass air conversion...this will fix your problem. It requires a new computer and some simple wiring and a mass air meter. It is a pretty simple swap
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
May 13, 2010
#7
  • May 13, 2010
  • #7
nicks87 said:
hello im new to the site.i have always loved mustangs how ever i have alway worked on classics. recently i bout a 87 lx 5.0 this past winter i did a b303 cam swap mass air conversion smog pump delete and pulleys.i start the car it runs good no miss, timeing is dead on,but after a few it slowly loads up i tried turning timeing back looked over all my work about a million times i dont have a computer to cheak for codes so i was wondering if any one could give me some advice or a direction to go thanks nick
Click to expand...

you dont need a computer to check for codes. look at the stickies in the tech thread and it will show you how to check for codes with a paperclip and a test light. I do it all the time and it works perfect.
 

old_blue

15 Year Member
Nov 3, 2003
1,783
282
124
May 13, 2010
#8
  • May 13, 2010
  • #8
http://www.stangnet.com/mustang-forums/698148-help-me-create-surging-idle-checklist.html


this thread shows you how to pull codes. let us know how it comes out.
 
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