93 Z28

[azwildoates]

I parked this car and the battery went dead. I have tried to start it and have spark, got fuel to the rail, can hear the pump, push the bleeder valve and have fuel squirt, but have no impulse to the injectors. I replaced the ECM with a rebuilt one and still no impulse to the injectors. I am lost, some one tells me that the chip in the key could cause this? and that I need to get it reprogramed? Thoughts

[FormulaLT1]

Does the engine turn over and had you tried to scan for troublecodes before you replaced the ecm?

[azwildoates]

Yes, it cranks, and I have spark and I showed no trouble codes

[FormulaLT1]

Does the security light flash or glow when turning the key?

[azwildoates]

Security has always been on, even when it ran. I always thought it was because the stereo was changed out or aftermarket alarm system installed.

[FormulaLT1]

Well according to this Vats will cause a no cranking sitution http://www.12vp.com/info_resistors.htm , So I doubt that its vats. Also how do you know that the injectors aren't pulsing did you use a noid light?

[azwildoates]

Yes I used a noid light on the injectors. That is why I thought my ECM was out.

[FormulaLT1]

I would check your harness grounds to make sure they not bunrt or split. Sounds like a electrical problem to me but you ran fuel pressure right?

Also welcome to the forum. Forgot to add that before.

[azwildoates]

I did not put a gage on it, but I can push the bleeder valve and it squirts fuel. I can hear the pump

[FormulaLT1]

Well fuel injectors would still be required to pulse no matter what the pressure was but its always a good idea to double check it... I would turn your ignition on pull your harness to each injector and look for a min of 10 volts. If there is no or less than this. use your battery as your ground on the test electrode and check the always hot side or postive injector wire. If after this method the voltage is correct. You have a ground issue. This would be my guess as to what is wrong. Good Luck.

John

[azwildoates]

I check the injectors and have no voltage. I check the ohms and have good between the contacts on the injectors and wires.

It is strange that it just happened when I let it set and battery went dead. It has a aftermarket alarm Python 700 series, could this be the fault?

[FormulaLT1]

Did you check your under hood fuse box?. And you also checked the voltage using the battery as your ground?

[azwildoates]

Have check all fuses, and yes, used the battery as ground

[FormulaLT1]

Well every alarm I know of either interupts the starter solenoid or Igntion coil(but call the maker of this unit and ask). So I highly doubt its that. So with the ignition on there should always be voltage to the injectors. The ECM uses the ground to complete a circuit and pulse them. So since there is no voltage the problem has to lie in the hot all the time pink line that splits to all the injectors. Your going to have to follow the line from the under hood fuse box to the injectors but just so you know there are 2 lines so even though the noid may have not worked on 4 injectors. 4 should still be pulsing unless you shorted out the whole box which I have never heard of before. Good luck.