So I finally got an ECM that works and I even managed to get it hookied up to my laptop. All the sensor readings show up, but there is no RPM reading while cranking and the injectors are not firing. I have tried several dist modules with no change. My question to you is: what is responsible for generating, processing, and then sendng the RPM signal to the ECM and is there a way to test it? Sound like somthing a new dist and module could fix? 730 ECU TPI THanks for any help! :lala:

The ECM receives reference pulses from the ignition module...sounds like yours isn't receiving them.

You've pretty much ruled the ignition control module out as a suspect. Next logical step is the wiring.

Check the grounds on the back of the passenger side cyl head. Even if they look fine and are tight, I'd remove them, clean the ring terminals and head surface, then reinstall. Then check the integrity of the ground strap from the engine to the firewall...same deal, even if it looks OK pull/clean/reinstall.

Let us know how it goes.

As measured at the ECM I get about 2.3 volts while cranking on the reference wire. Goes to 0v like it should when I stop. As tested at the ECM, all the grounds seem to be grounded, but I will go over them again just to make sure. Thanks!

TTT I really need help!

Could be the VATS system keeping the injectors disabled. Also make sure the injctors receive power (pink/black wire) while in the crank position. The ECM grounds the injector circuit to fire them. When I use Datamaster or Tunerpro RT on my 730 $8D based bin I don't get an RPM signal while cranking.