1990 Full Size Blazer No Injector Pulse.
I replaced the distributer, replaced the ECM and fuel pump is good. What next?

 

How did you confirm you have a "no pulse" condition?

 

Also, do you have power to the injectors? Did you check with a noid light?

 

By troubleshooting it with the noid,

 

So you have power to the injector but no low side ECM pulse control/switching?


George

 

Tell me more about he low side, never heard of it..

 

The way that fuel injectors work is to apply fused ignition power to one side of the injector coil and then take the other side and send it to the ECM which then controls the grounding of that side of the injector coil to create the duty cycle necessary for proper air fuel control. So the control of the injector is ground side switching by the ECM.

If you have improper fuel delivery then you either have:

Improper ignition power applied to the injector on the powered side

Improper ground side control of the injector by the ECM on the ground side

Bad wiring/connector

Bad injector

Fuel pressure issue


George

 

And if you have no ECM ground side switching the either the ECM is dead, there is a wiring/connector problem or there is a sensor input problem to the ECM for pulse timing like from a crankshaft position sensor.


George