o.k. I have a 5.7 350 w/aftermarket cam, pistons, bored.30 over. It has been timed and the VATS bypassed correctly. All the systems are working correctly except injectors/ no pulse? here are the things i have checked

1. 12v to both sides of the injectors
2. 12v drops to 6v when engine turns over
3. ignition module was checked by parts store/ brand new dizzy
4. TPS shows 4v+ almost 5
5. ECM appears to be functioning properly
6. Fuel pump is primed and pressurized
7. Engine ground is good
8. Spark plugs have fire

If I am missing something please advise...

 

I recently had a problem with the ecm leaving the injectors open and it turned out to be the ecm itself. I would try another ecm.

 

either the ECM or ignition module... just because it tested good doesn't mean it's good... ..

 

If your TPS is showing 4v with the throttle closed there is something wrong with it. The ECM goes into "clear flood mode" if it sees that much voltage from the TPS while cranking, shutting off the injectors. It should show .54v with the throttle closed. Replace or free up the TPS and you should be ok.

 

 

Ok here is a stupid question, would a custom programed prom cause this problem? the car had an an after market msd box on it...i took it off when i bought it so i could return it back to factory to trouble shoot other problems w/the car. but then i noticed that the prom had an aftermarket sticker over the glass part on the prom...two race flags with performance something or another on it... so could this be the problem...do i need to wire it back up?

 

Have you fixed the tps yet if not do that immediately and then test the pickup coil as it has alot to do with injectors firing. Are you one hundred percent sure the injectors are not firing and how are you testing for this? Try disconnecting your ecm find a pinout diagram and see if you can manually fire the injectors to rule out broken wires.

 

wondering what did u use to bypass the vats???????
is ur check engine light on??

 

Where are you seeing this voltage drop? If it's at the inj. harness then it sounds like the ECM is doing it's thing and controlling the inj. The next logical step would be to check the fuel pressure at the rail. These TPI engines require at least 35 psi to force the fuel through the inj. Also check the voltage going back to the pump.