Here's my problem. I converted over using a 727 ECM. I know, I had to be different, but it's what I had. Anyhow, for some reason now I've got ground on the ground side of the injectors all the time. It never pulses. I've got the ground hooked up in the D9 and D3 terminal at the ECM and a ground source in D4 and D10. Did I mess up or is it possible the injector drivers are bad in my ECM? Please help! Thanks

 

As I recall the 727 just uses one injector drive. An ohm meter will tell the tale.

Go from + to a 1K reistor to the ijector pin at the ecm. If the light is always on, then the ecm is commanding the injector to fire.

Usually an injector driver goes open, or erratic.
I don't recall ever seeing a shorted driver, but it could happen.

 

Only uses one driver? Maybe that explains it. The dang schematics show 2 drivers. I'll try to wire it up one at a time then, see what happens. Thanks and merry christmas!

 

According to the Helms Diagrams...

D9-Injector driver-Injectors 1,3,5,7-INJ 1 fuse

D3-Injector driver-Injectors 2,4,6,8-INJ 2 fuse

D4-Injector Ground

D10-Injector ground

D4/D10 have a common common once outside of the ECM.

 

Ok, here's what I found. With everything plugged in I've got power and ground to the injectors. Unplug connector D from the ECM and my ground goes away. With D plugged in but pin D3 out, I have no ground. So I'm pretty sure that the injector driver is bad or I'm getting an incidental ground somewhere inside the ECM. Sound like the right ASSumption to you guys? Thanks for the help!

 

Did you check for a blown fuse?

 

Blown fuse to what? I've got a constant 12 volts to one side, and a constant ground to the other. From my understanding the ground should not be there constantlt. It should pulse when the computer commands the driver, which would fire the injectors. This is my understanding, am I wrong?

 

Sorry man...I had one helluva good idea planned out for you. Went to try it out on my car and realized that either my setup is messed up from the repinning or I'm just too tired to be messing with electricity right now.