94 GT Convertible Project GT40P, B303, etc

[DMG1]

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]

My first thought would be to remove the Quarterhorse and see what the stock computer gives you if that's possible.

 

[Mustang5L5]

What is the QH doing? Is it calibrating for larger injectors and a stock MAF?

 

[DMG1]

My first thought would be to remove the Quarterhorse and see what the stock computer gives you if that's possible.

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.

 

[DMG1]

What is the QH doing? Is it calibrating for larger injectors and a stock MAF?

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]

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.

 

[DMG1]

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.

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.