DOHC swap help

smith020208

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I need some help with my 04 gt 4v swap. I took the engine out of a running mark VII and I have a 98 cobra intake on it. I have the install completed. Wiring done too. But the car won't start. I have have checked for spark and all plugs are firing. I have checked for fuel and it is getting pressure and I have checked the injectors are pulsing with noid lights. I have run the crank no Start checklist and cannot figure this out. Please help before I light this car on fire.
 

smith020208

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I just swapped over the SOHC stuff like oil pan etc. I used the SOHC wire harness and swapped the polarity for the COPS and extended the wires.
 

hotcobra03

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Were the injectors also reverse like cop?

Side note,

We have a 2010 tundra. We have issues with squirrels or something getting into engine bay chewing wiring harness

We had a no start issue, I had spark and fuel and it cranked with key.

Found a few wires chewed by pcm ,guess theft mode may have been cause ,

But I was like you, why won't this thing fire up
 
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smith020208

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I am running the ecu from the mustang and I did not reverse the polarity on the injectors. They are the same injectors that came with the mustang from the factory.
 

Blkkbgt

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I am running the ecu from the mustang and I did not reverse the polarity on the injectors. They are the same injectors that came with the mustang from the factory.

This is wierd because from my understanding of 4v swaps the car should start.

There has to be a signal the ECU is looking for that it's not receiving.
 

SecondhandSnake

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How/where did you check for fuel pressure? Sometimes they can take awhile to fill the rails completely and work the air out. Even if you key cycle it to prime it a few times. You just have to keep cranking periodically to get it to light. Opening the shrader valve until you get fuel can help bleed it some.

Also since you extended the coil wires, you might double check and make sure that you didn't mix any cylinders up. Even if you did mix a few up, you should get some popping and banging when you crank.
 

decipha

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Get yourself a moates quarterhorse direct from moates.net

Plug it in to the back of the ecu and you can see if the crank sensor, cam sensor etc.. is working and if they are syncing or not as well as if its in theft mode etc...

It will show you your fuel pressure and actual spark if all is functioning correctly.

You can also disable theft with it to test if the theft system is acting up as well.

On the plus side that same diagnostic and datalogging tool is also an emulator and real time programmer / tuner that your tuner will need to properly dial in the vehicle too so its a win/win.

Getting Started / EFIDynoTuning
 

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