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

94 GT Convertible Project GT40P, B303, etc

  • Thread starter Thread starter DMG1
  • Start date Start date Aug 23, 2020
D

DMG1

Member
Aug 4, 2020
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1
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Mt Pleasant, Pennsylvania
Aug 23, 2020
#1
  • Aug 23, 2020
  • #1
I just traded for a friends project car. It’s a 94 GT Convertible Cobra clone with GT40P heads, B303 cam, Moates quarter horse, 4.10s, 5 speed, etc.

the car supposedly has a base tune on the Quarter Horse and It runs poorly. Won’t idle. I would like to run codes but when I try to use my Snapon scanner it won’t communicate. When I jumper the 2 plugs on the under hood diagnostic connector, the engine light doesn’t flash.

I suspect the TPS wiring is not correct but alldata doesn’t give good info on the connectors.


My big issue is that I can’t run codes. Is the Quarter horse causing the problem? Anyone have an idea?
 

Ryuk

I love your drawers
5 Year Member
Apr 22, 2017
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Aug 24, 2020
#2
  • Aug 24, 2020
  • #2
My first thought would be to remove the Quarterhorse and see what the stock computer gives you if that's possible.
 
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Aug 24, 2020
#3
  • Aug 24, 2020
  • #3
What is the QH doing? Is it calibrating for larger injectors and a stock MAF?
 
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DMG1

Member
Aug 4, 2020
4
1
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Mt Pleasant, Pennsylvania
Aug 24, 2020
#4
  • Aug 24, 2020
  • #4
JD08 said:
My first thought would be to remove the Quarterhorse and see what the stock computer gives you if that's possible.
Click to expand...
I removed the QH. Now the check engine light is out, the car idles and the cooling fan no longer runs whenever the key is on. Good news, maybe.
 
Reactions: Ryuk
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DMG1

Member
Aug 4, 2020
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Mt Pleasant, Pennsylvania
Aug 24, 2020
#5
  • Aug 24, 2020
  • #5
Mustang5L5 said:
What is the QH doing? Is it calibrating for larger injectors and a stock MAF?
Click to expand...
I am not 100% certain. I think it is calibrating for the cam, headers, etc. I need to buy the big MAF and 460 injectors before the final Tune. I have been trying to address other stuff first like being able to scan for codes and look at data.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Aug 24, 2020
#6
  • Aug 24, 2020
  • #6
Troubleshoot without the QH for now. ID what injectors/MAF you are using.

By buddy built a Fox with that same combo (GT40P, B303, 4.10's) and it ran awesome with a stock A9x ECU. I know the SN95 ecu is a bit more finicky for cam swaps however though.
 
D

DMG1

Member
Aug 4, 2020
4
1
13
Mt Pleasant, Pennsylvania
Aug 24, 2020
#7
  • Aug 24, 2020
  • #7
Mustang5L5 said:
Troubleshoot without the QH for now. ID what injectors/MAF you are using.

By buddy built a Fox with that same combo (GT40P, B303, 4.10's) and it ran awesome with a stock A9x ECU. I know the SN95 ecu is a bit more finicky for cam swaps however though.
Click to expand...
I am running the wrong MAF and injectors at the moment, I think I need to get a set of 460 injectors and a BBK 76mm MAF.
 
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