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

just converted to mass air, not running right!

  • Thread starter Thread starter Mean88
  • Start date Start date Nov 6, 2004
M

Mean88

Founding Member
May 13, 2002
656
0
16
Nov 6, 2004
#1
  • Nov 6, 2004
  • #1
I just converted my car to mass air. I upgraded the injectors to 30#s to better match my combo as suggested by members of this forum. I also have a 75mm pro m with the correct calibration. I used the pro m conversion harness and a a3m processor to run the engine. The car idles fine, but under light load it stumbles badly, and cuts out. If I mash it down it runs good. I am running about 40# of fuel pressure at the rail vaccum off. It seems to have a light tip in throttle leanness. Since I havent dealt with the mass air proccessors, or the meters, what are some good things to check to ensure I didnt overlook anything when i assembled it? Any info is welcomed
Ted
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Nov 6, 2004
#2
  • Nov 6, 2004
  • #2
Make sure the map is not capped and the vac line from it to the manifold IS capped, also look for vac leaks EVERYWHERE. Also heard rumour about conversion needing some wiring changes or pin changes for the VSS sensor to work properly.
 
M

Mean88

Founding Member
May 13, 2002
656
0
16
Nov 6, 2004
#3
  • Nov 6, 2004
  • #3
Map sensor is without vaccum and the line is plugged. The car really intermittantly stubles pretty badly. Anyone else??
 
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