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99 GT, Sean Hyland cams, Kenne Bell 1.7. First a little background..I just finished replacing the front engine/timing cover. (long story) but it had an SCT timing adjuster that I removed and simply plugged in the crank sensor. Started the car. It's missing at least one cylinder and is dumping fuel into driver side exhaust. So much, it was spewing out between the collector and the manifold connection. One of the collector bolts was loose so I tightened it up, restarted, and got a huge backfire. Sounded like gunfire. Haven't restarted since. Called local Mustang speed shop, he, without hesitation, said to change the battery. Haven't tried that yet, but did clean all of the ground connections. I then was inspecting the FI harness and someone at some point spliced in a wire to every fuel injector. all of those wires culminate at a plug that isn't plugged into anything, but every pin has power in the run position. Why would someone do this? What may have it been plugged into? In photos its all of the orange wires. The other question regarding that timing adjuster, would the car have been tuned using that thing? Would they have advanced or retarded the cams themselves and then dialed it in with that adjuster? I'm hoping the backfire was just the build up of fuel in the exhaust. Thanks for any insights. JB.
 

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Did you get the fueling to quit spewing out the exhaust?
If not then it's very possible that the negative wire on that coil is shorted to ground. I had this problem too. Get a Noid tester ($20 and at parts store) and plug it into that injector wire. Turn the key on and if that noid lights up then that ground wire is shorted against the block or ??.

Been there, done that.

ks
 

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If anything, I believe the injectors are working TOO well. This is more of an ignition, wiring, computer issue. Correct me here, but are you explaining that if a cylinder isn't firing, that injector should shut down? I also have an '03 Centennial Mustang with a Procharger that developed the classic coolant crossover leak and fryed the #5 COP. All I had was a misfire. It didn't continue to dump fuel into the exhaust. I did rent that Noid light and will mess with it tomorrow. From my original post, did you have any thoughts on why someone would splice into every injector? Thanks!
 

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Yes, if a cylinder isn't supposed to fire at low RPMs then that injector should not be firing. If you plug the noid in then it will blink while the engine is running if operating properly. If it stays on then the ground wire may be shorting out against the block/head/?? and that injector will be wide open and never close flooding the engine.
I have 80# injectors on my car and the ground wire rubbed through on the engine block on one injector causing that injector to fully open. Let me tell you, 80# injectors flow a LOT of fuel in a very short amount of time! I must have had a gallon of fuel in the exhaust in 30sec..

If they tapped into the 12v side of the injector wires then they may have been doing some trouble shooting and they needed to control the voltage to them.. I dunno.

ks
 

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A couple questions, why was the adjustable timing gears taken out? If it was degreed in properly, it would be necessary to retain for the camshaft position sensor to fire the coils. I have seen a fueling issue such as yours and it's almost always contributed to the ignition side. Not sure the why the wires were cut and spliced, but it almost makes a PCM pinout diagram impossible to diagnose. Like what was said earlier, a noid light will test voltage firing the coil and injectors. But something tells me that the adjustable cam gear should have been left in. It ran fine before, and now it's causing issues.
 

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from the picture, it looks like all the ground control wires are tied together, NOT the power, the different colored wires is the ECM ground side switch to each driver.

this would make it a batch fire........redo it all
 
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