Chevrolet Repair: 1992 Chevy S-10 Blazer TBI, chevy blazer, pulse width

Question
Sir, I have a 1992 TBI Chevy Blazer with only 1 Injector working.The passenger side injector does not spray. When problem first started it would work intermittently,Now it does not work at all. I have replaced the ECM and checked the pigtail connectors. What are your thoughts ..thanx  
:)

Answer
Hey,

 First check the resistance of both injectors.  A shorted injector will take out the ECM in no time.  They are 'peak and hold' injectors.  You should also look very closely at where the injector wires go through that little clip that holds them to the throttle body where the air cleaner bolts on.  They get pinched there and you will see a 'dent' in the wire.  It won't be stripped but will have no continuity.
 IGN+ is supplied to the injector and the PCM uses a negative potential to duty cycle the pulse width.  At an ambient temperature of 20c the resistance of the injector should be 1-2ohms.
 Do you have a low amp probe and graphing meter?  I can show you some need tricks on how to identify pintle problems with a vantage and current ramping tests.  I have developed an excellent trigger event test using the EST signal from the ignition module.

Wayne