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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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help with speed density car

  • Thread starter Thread starter glocktoys
  • Start date Start date Jun 19, 2005
G

glocktoys

New Member
Jun 2, 2003
14
0
0
indiana
Jun 19, 2005
#1
  • Jun 19, 2005
  • #1
i am checking my info on the car now. the guy that sold me the 1986 mustang gt stated it had been rebuilt, had a mild cam and gt40 heads. i have to take a weekend to tear the car apart to see about the heads and slugs but was wondering about getting a chip for the car. it runs quick and pulls into the 6500 rpm range so it may not be stock but has a idle problem (up and down and idles high most of the time). i replaced the tps and car and rotor, plugs and put ned gaskets on the egr and throttle. i also replaced the fuel pressure regulator. still high and low idle. tested system with code scanner with koeo no problems and key on engine on gave me a no cylender information recieved error.any ideas?
 
J

jerryD

Founding Member
Mar 16, 2000
1,061
0
37
Gladstone, MO
Jun 19, 2005
#2
  • Jun 19, 2005
  • #2
you need to convert to mass air. the speed density cannot compensate for the heads and cam.
 

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Jun 19, 2005
#3
  • Jun 19, 2005
  • #3
I have the same problem with my SD car. Thing is, mine is stock. If yours is modded, that's the problem. The cam will really screw up the vacuum properties and confuse the MAP sensor. You need to either get a custom chip or convert to mass air to fix your problem.
 
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