Electrical Stock Ecu Woes

[MikeH686]

so I've since begun switching over to stand alone aftermarket. The reason for this is because of my stock ecu taking a crap on me. Reason for posting this is has anyone ever had the ecu just stop signaling an injector to fire? I had the #6 injector stop getting called to fire off by the ecu. I found this with a noid light, then with a dvom I ohmed out both the power and ground wire and both have good continuity even through the computer connector. It's the weirdest thing of all things to stop working be a injector.

 

[jrichker]

The injectors depends on the computer to provide a ground to complete the circuit and make the injector spray when the intake valve opens. No computer provided SWITCHED ground and the injector doesn't spray. Not strange at all, considering that if the injector shorts internally that it wipes out the transistor in the computer that controls that particular injector. There are 8 injectors in the 5.0 Fox Mustang EFI series computers and 8 power transistors to control them.

Having the computer serviced to replace the defective transistor is a lot simpler and cheaper than putting in a whole new system and getting it running good. Check out eBay for companies that repair the Ford EECIV series computers. You send them money and the computer, they send you back the same computer repaired and with a guarantee. Or check your local auto parts store for a reman replacement.

 

[MikeH686]

Oh the Holley system is already in and wired up, I started this as thinking it was just a weird thing to have go array, but you are right if the injector went bad that the computer would be affected