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Discussion Starter · #1 ·
Hello all. New member here. My father in law as a 1994 Camaro Z28 with an LT1. We have a very interesting issue. The Car was running terribly and finaly quit. Tried to start it and it snapped the nose cone off the starter. Pulled the plugs and #5 poured fuel out of it. Fast forward, 8 new injectors, new starter and oil change, it is still filling #5 with fuel in just a few revolutions. I am now stumped.

HELP!
 

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Welcome to the forum. Sounds to me like a rare PCM problem.

How the fuel injectors work; Whenever the key is turned on 12 volts is sent to all the fuel injectors. To make them open, the PCM applies a ground to each fuel injector when it's supposed to open & spay fuel.

My best educated guess is that PCM is applying ground all the time on cylinder # 5. Fuel injector is open all the time that key is on.

To test my theory, buy a set of noid lights. Available at harbor freight & auto parts stores. Test a cylinder that is working correctly. When new starter has been installed, remove spark plug from cylinder # 5. This is so fuel has a place to go as test is performed. Have assistant crank engine while you look at noid light. It should blink on & off. This is your control observation in this experiment.

Next, hook noid light to injector #5. With spark plug still out, have assistant crank engine. I'm betting noid light will be solid on.

If my hypothesis is correct, you will need another PCM. If incorrect, we will have to delve further into this.

Right now, the only other thing I can think of is that wire from cylinder # 5 is shorted to ground. This would also cause constant fuel flow.

Here's a link to 94 factory service manual. It has full wiring diagrams to help trace # 5's injector wire to the PCM. www.mediafire.com/?40mfgeoe4ctti
 

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Discussion Starter · #3 ·
Well, the car has been sitting a while and went to paint. It just so happens that there were signs of Palm Rat nests in the inner fenders when they took it apart. Could a chewed wire cause this?
 

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If a rodent chewed the # 5 injector ground wire, which comes from PCM, if it is grounding to metal somewhere, yes the fuel injector will spray fuel anytime key is on.
 
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