will an engine harness from a 87 turbo II work with my 88 turbo II?

 

i also noticed that it had an extra wire that is attached to some kind of metal piece by the airflow meter plug/

 

Yes it will work, the "metal piece" is the resistor pack for the fuel injectors. You will notice that your injector plugs are going to have a different slot than your injectors. You should swap your fuel injectors out for low impedence 550's your current 88's are high impedence.

 

All you have to do to the 87 harness to make it work with the 88, is disconnect the Solenoid Resistor Package, put it on the shelf in the garage.

Then jumper ALL FIVE wires in the connector on the emissions harness together.

Actually, to keep from hacking the emissions harness, you could cut the solenoid resistor package harness in half. Then reconnect the solenoid resistor plug to the harness. THEN strip the five wires on the solenoid resistor plug half and join them, all FIVE together. Done and you have not hacked the emissions harness at all. I've done this on one 87 car of mine that I put the high resistance injectors in off a 88.

 

See this thread and the jpgs attached to my post there. https://www.rx7club.com/forum/showth...sistor+package

EDIT: Another of my OOOPs. That thread was for changing just two high resistance injectors into a 1987 low resistance car. For you, you'd cut ALL FIVE wires about where I did in the pictures. Then splice all five together and cover with heat shrink etc and then plug the large yellow plug back into the emissions harness. Done. It'll work plenty good fine.

 

so i cut all five wires and crimped them together. do i have to bolt on the soleniod resistor on to my car?

 

NO. The solenoid resistor gets put on the shelf.

Hold the solenoid resistor in your hand. IT has the plug on one end and the aluminum covered resistors on the other end.

CUT that harness in two. In the middle would be fine. Put the aluminum covered resistors on a shel in the garage.

Strip all five wires on the half of the harness that now just has the large plug on it. Crimp all five wire together. Then reinstall the crimped wires with the plug back on the emissions harness. DONE.

Four of those wires go to each of the fuel injectors. The fifth wire is a 12vdc source. You want it to feed those other four wires, so you crimped them all together and covered it with shrink tubing or whatever.


The fuel injectors work by that plug feeding 12vdc to the injector and the ECU putting a pulsed ground on the OTHER wire on the fuel injector. In other words there is 12vdc on each injector all the time. The voltage is not the item that gets pulsed, its the other wire on the fuel injector that gets a pulsed ground from the ECU.

I might jpg what you need to do later this night if time lets me.

 

Attached is a jpg of two items. One is what you start out with. The other, surrounded in a red border is what you end up plugging into the emissions harness. I can't explain this any better.

 

perfect, you are the man. i crimped them all together and still left the other side hooked up. tomorrow i will do it as it is in the picture. ill let you know what happens.

 

Just in case............after you crimp the five wires together and then install the *device* on the emissions harness, you keep your original 88 high impedence fuel injectors. You don't put in low impedence injectors for this. If you decide at a later date to put low impedence injectors in the engine, then you have to use the solenoid resistor package in the same form it was originally.

 

STHJ

So in a case where I am using s5 injectors on a S4 harness, I would just splice the s5 injector clips onto the s4 harness, do your modification and call it a day?

 

Yes, exactly.