injector wont fire

[LordOfTheMiasma]

my number 4 injector wont fire at all. car runs fine.. just only on 3 cylinders. there is power coming out of the ecu from the blue and black wire. when i check the wire on the plug that goes into the injector there is half the power of the other 3.... i have no idea. the wire isnt broken anywhere. any ideas would help greatly.. please help me....

[LordOfTheMiasma]

cmon someone needs to help me paleeeeese... or there will be one less 240 on the road when i set it on fire...

[IanS]

is there an injector pulse at the ecu, No = bad ecu

Yes,

is there injector pulse at the injector, No = wiring problem

Yes,

is there ground at the injector , No = bad ground

Yes,

if you have all three, then you have a bad injector

[LordOfTheMiasma]

i swapped the injector with 4 other ones.. one at a time.. where would the ground be bad?? the injector has a pulse and it seems like the ground is bad.. where the hell is the ground for it?? there is the red wire.. which is the positive.. and the blue and black that is the ground correct?? both go nowhere but to the ecu correct?? there is pulse coming out of the ecu on both wires but half at the injector... where would i check the ground??