I need confirmation on voltage read out.
When measuring for voltage, I get 12v on the black wires on each injector and no voltage on signal wire. I believe that the ECU controls injectors via shorting ground, is that correct?

 

Follow up question, what should reading should there be between the terminals of the injector plugs in igntion on position? I am getting 12 volts on injector 1 & 3 across the pins and nothing on injector 2 & 4.

 

Sounds like an mpfi conversion?

 

Correct. ECU sends ground pulses.
Take the distributor off and rotate it by hand.
You might see a pulse jump by... or you might not.
Correct tool is noid lights.

 

thank you for the info.
not a MPFI conversion, ITB install. ended up being two injectors clogged.