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'79 EFI Fairmont running rough

  • Thread starter Thread starter rxracer
  • Start date Start date Apr 22, 2012
R

rxracer

New Member
Sep 26, 2004
8
0
1
Apr 22, 2012
#1
  • Apr 22, 2012
  • #1
'79 Ford Fairmont 4-dr
EFI 302 from 95 GT
'91 mustang wiring harness(two plugs at booster)
A9L
Explorer MAF meter
fox upper intake
fox distributor
fox throttle body and EGR spacer
fox headers
All stock except E303 cam and Paxton adjustable FPR(40psi vac line off)
Mark VIII electric fan
6G alternator
V8 4R70W trans
12" stock V8 converter
Optishift controller
2.5" y-pipe into single 3" straight through muffler
no cats
no smog
no EGR valve
8.8"
3.55 gears

Replaced:
PIP, fuel filter(Russell billet 40-micron 6AN), fuel pump(Airtex E2000), plugs(Autolite 25's), wires(Xact 8MM), cap, rotor, TFI module, coil, thermostat(195 degree), MAF(from a 95 GT, ran worse), computer with A3M, TPS is good(Optishift monitors/displays voltage), All grounds are connected

Problem:
Motor will run half-ass if base timing is above 20 degrees. Spits and stutters or dies if timing is set lower in park or in drive. Very laggy throttle response, and under load revs are not clean. Also feels like it doesn't have any power.

KOEO codes:
34
67
and a bunch of codes in the 80's(no EGR or emissions related stuff installed and fuel pump is wired on a switch)
EEC will NOT perform KOER test(tried 3 different scan tools plus a test light)

Thoughts?
 
R

rxracer

New Member
Sep 26, 2004
8
0
1
Apr 22, 2012
#2
  • Apr 22, 2012
  • #2
And compression is 150psi on all cylinders.
 
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