Hello,

I am wireing in a fjo injector driver. I searched for this about wiring, but just wanted to confirm this issue. Is the pin on the ecu that provides the 12v constant power to the injectors pin 4L? I am a bit confused because in the factory wiring diagram it shows that 12v source going off to a relay.

Thank you, I just really don't want to fry anything.

 

the ECU is the GROUND. the power feed is from the battery to one of the fuses in the underhood fuse box, to a relay to the injectors to the ecu to ground.

on the FC there is a "main" relay that turns on all 5 power circuits at once (efi power, emissions power, the lighting, interior and something else that doesn't go bad) the FD might just have separate fuses.

the injector wire is black with a yellow stripe. the emissions/BAC/AWS/solenoids is back with a white stripe.

so again the ECU does NOT supply power, it supplies the GROUND.

 

So how do the fjo guys tap into the power to the injectors? Rewire the injectors?

 

Ok I get it. You're doing this:

http://www.fjoracing.com/products/injdrvr/

So I think what you're looking for is Step 9:
So it's saying that the power for the FJO injector driver is coming from the same relay that drives the injectors. That's pretty easy to accomplish. You don't have to rewire the injectors. Just tap into that relay.

 

12V power for the injectors is supplied by the EGI main relay. It enters the engine harness at connector X-05, which can be found forward of the ECU along the firewall in the the passenger footwell. It is a B/O wire on the dash harness and B/Y wire on the engine harness side of the connector.

 

Dang... someone knows their stuff. I'm impressed.

 

That is exactly what I am looking for! Thanks for the information Banzai!
Btw your oil pan brace rocks!!

 

Good info here.



(the following is not necessarily related to the FJO install
The engine-harness side of the connector (B/Y wire) uses the same exact female pin as the 'large' ECU pins like the injectors (4X, 4Y,4Y, 4Z). These pins are relatively easy to obtain, they're also used for the ECU found in OBD1 Hondas, 2G DSMs, and EVO8's). If you have the engine harness apart, it's possible to de-pin and remove the original injector wiring (including both power and signal) and replace it with brand new wires and pins for a very clean install of aftermarket injectors that require different connectors.