blown7

Ok so here is the poop. I'm stripping down my '84 GSL-SE for its engine swap. I have already pulled the engine and transmission. I know which wire's I need for sensors, starter, transmission. I'm installing my 13B-PP into this car and would like to prune the wiring harness. The engine harness on the passenger side can pretty much go except i found a large black with yellow wire that seems to link up with pretty much everything. It's soldered together at a bunch of spots as it routes from the passenger side over to the driver side. It is a 10 gauge black wire with yellow strip. It is connected to the injector caps, ignitors, coils and ECU. My question is, is this wire switched 12V. Can i rewire it so it goes to the ignitors and coils from a switched 12V source. Also can i fully remove the ECU from the car as the only engine related wires required are the alternator, ignitors and coils. I'm running a mechanical oil pressure gauge and water temp. Thanks in advance.


I have looked at foxed.ca in the wiring diagrams for the car and i think i confused myself.

mazdaverx713b

iTrader: (91)

you can test the wire for switched power by simply using a multi meter... i think the wire you are describing may be a ground...i'll double check the wiring diagram..is it the wire that is junctioned together near the distributor?

74RX4

iTrader: (10)

Sounds like the wire from the main relay. If so it is switched 12V.

The 2 black, rubber covered cylinders in the engine compartment, near the firewall, on the far left, are the main relays. One supplies switched power to the injectors and the other supplies switched power to the coils. The one for the coils connects to plug B-33. This is a four wire plug. The Black/yellow wire goes to the + terminal on both coils and ignitors. The White wire is constant 12V. The Black/white wire is switched 12V. The Black wire goes to ground.

84stock

iTrader: (5)

I've been thinking about unwrapping the nest of wires I have tucked under my hood from the efi to see what i can get rid of too, keep this updated with pics too please. Ooooh, and answer my pm's......good luck with the swap.