Cadillac: Eldorado wiring system (ECM/FI), cadillac eldorado, liter v8

Question
I have a 1990 Cadillac Eldorado with a 4.5 liter V8. Got approximately 145,000 miles on it. Problem before me is this - All 8 fuel injectors are not firing. I had one point where it was only running on 4. A friend of mine piggy backed a few wires and got it to run on 5 or 6, but I need a second opinion. I've been told this could be the ECM and/or fuel rail harness doing this. What do you think? I'd like to drive this for the winter, so your help would be appreciated. Thanks!

Answer
UNDO that piggy back repair befor you damage the engine.

Are you getting a check engine light on the dash and if so, What codes are you getting ?.

Is your fuel pressure between 40 and 50 psi ?.

Check the fuel pressure FIRST.

I can e-mail you pictures and directives on how to use the on board diagnostic display via the climate control panel to test each injector to see which ones are and are not working.

Contact me AFTER you undo the above and test the fuel pressure at: onlineautohelp@msn.com