1SlowBB2

I'm currently working on a 95 DC2 GSR that had be heavily modified by the previous owner. Right now as it sits it has a LS motor (without vtec of course) running on a P75 ECU. On ECU plug A there are two wires tied into the harness at A25 (IGP1 Power Source) and A26 (LG1 Logic Ground). My goal is to eliminate these wires that he tied in, yes tied in, not cut, and trace the original wires back to source to find out why it won't work on it's own.

Anyone know where these 2 wires originate from?

da93teg

A26 ends up at the thermostat ground location
A25 is yellow/black and it runs to main relay

Hope this helps

1SlowBB2

Thanks for the reply. I found the other end of A26, or at least I believe I did. Ohm test read some outragously high number but the car ran perfect with me grounding the other end. A25 is another story. There's no power to it with key on or off. I can run 12v to it and it will work fine. I did an ohm test between the ECU pin and a yellow/black wire over at what I believe is the main relay under driver side dash, read 2.7ohm. That yellow/black wire is 2 wires together going into the back of a plug and has constant 12v key on or off.

I'm also showing a code 1, just 1 long blink followed by long pause over and over. Resetting the ECU now to see if that goes away. Any more ideas?

Also, this Chilton's wiring schematic is showing that it just needs a 12v source with the key on, is this so?

da93teg

The code 1 is actually a 10 a long flash is a 10 a short flash is a 1
Code 10 is for the o2 sensor not a really big deal but it should be hooked up and or replaced
A26 should be a ground at all times
And A25 shold be hot until the coil inside the pgmfi main relay is energized then it should turn to ground to complete the circuit of the relay

If you can trace the wires that are tied in from start to end and give me a little more info ill be able to help more

da93teg

And 2.7 ohms is alot of resistance id check for an open in the original wiring that may be the reason for the added wire

1SlowBB2

Fixxed. Thanks for the input.

da93teg

No problem

1SlowBB2

Another issue I'm running into is the car is setup for OBD1, but the rebuilt LS I put in there has a P75 OBD2 head, which means my OBD1 disty can only bolt up with 1 bolt. Any solutions to this?

1SlowBB2

Or are the ears on the disty different because my head is non vtec and the disty came off a GSR?