Here is the first plug (obd0). The top 4 wires are injectors right?(the 2 yellow ones and the 2 pink ones)


Here's the problem, on the driver's side firewall, only 1 color of each runs into the engine bay. The other yellow wire thats going to the engine bay looks like one of the wires I need, but it is going straight from a plug on the dash into the firewall. The other pink wire is nowhere to be found. Am I doing something stupid? Are all 4 wires supposed to end up at the firewall?


The problem is that I'm using and obd2-obd0 conversion harness. The car is an si, but somewhere along the line it ended up with a dual point motor. Looking at that first plug, it should be an si right? Wouldn't 2 of the plugs be open? At first we thought the si harness got traded with a dual point harness, but it looks like he just cut it and went back to dpfi with this harness. I'm just trying to get back to mpfi.

 

on dpfi cars, the yellow and red plugs split into 2 inside the car. since the car only has 2 injectors for 4 cyls firing at different times, they need 2 different signals each. if you look hard enough, you will find where they split. then you will have to run a new wire from each yellow and red wire to its new respective injector. the new colors should be blue and brown i believe... my dx harness looked just like yours with the 2 yellow and 2 red and my si is burried right now so i have no way of checking what color the wires are at the ecu on that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by skittyscott &raquo;</TD></TR><TR><TD CLASS="quote">on dpfi cars, the yellow and red plugs split into 2 inside the car. since the car only has 2 injectors for 4 cyls firing at different times, they need 2 different signals each. if you look hard enough, you will find where they split. then you will have to run a new wire from each yellow and red wire to its new respective injector. the new colors should be blue and brown i believe... my dx harness looked just like yours with the 2 yellow and 2 red and my si is burried right now so i have no way of checking what color the wires are at the ecu on that. </TD></TR></TABLE>

yep blue and brown are the correct additional colors.

 

Sorry, that was kind of confusing. They split? Wouldn't that become 8 wires?

Anyone know for sure if this is a Si or DX harness from looking at that plug?
On my wiring diagrams, it looks like an si harness based on what pins are full, and which ones are open.

 

that is a dx harness

when i did my wiring instead of using teh existing wires i just ran all new wires to make my own inj harness

i e-mailed you a pic that should help

 

If I'm converting to OBD2, don't I bypass the resistor box? What do I do, tie all 4 injector grounds into that 1 wire that's supposed to go to the resistor box?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 808BMW &raquo;</TD></TR><TR><TD CLASS="quote">Sorry, that was kind of confusing. They split? Wouldn't that become 8 wires?

Anyone know for sure if this is a Si or DX harness from looking at that plug?
On my wiring diagrams, it looks like an si harness based on what pins are full, and which ones are open.</TD></TR></TABLE>

well, it depends on how you look at it... from the engine bay to the ecu, they split into 2 wires each and from the ecu to the engine bay, they connect together... to understand the wiring, you need to understand how the motor works... with dpfi, there are 2 fuel injectors for 4 cyls. therefor, one injector needs to have 2 different signals sent to it for each cyl and this is why 2 wires turn into one...
by the looks of it, its a dx harness. like i said, im not sure but i think the si harness has a blue and a brown wire that goes to the ecu. it may be that the red and yellow wired go to the harness and then they are turned to blue and brown. besides, why would anybody wanna turn an mpfi car into dpfi?

as for turning it into obd2... im not too sure on what you have to do there. i would just be ghetto about it and hook up an obd2-1 harness and then a obd1-0 harness . if i were you, i would read a lot more before jumping into it and also consider converting your motor to obd1

 

Go obd-1

 

I already have a obd2- obd0 harness, I just need to wire the injectors because this is a dx harness. I just need a definate answer on what to do. So far the only idea seems to be run 4 new wires from those pins, and hook up all the grounds for the injectors to that 1 ground coming out of the harness (A14?).