I thought the 87-88 were the same? And the 89-91 were the different ones. Because I know the 89-91 dont have a resistor pack. But if you have a resistor pack in your car then your running low impedence injectors, 87-88. And the 89-91 have a high impedence injectors. I think this is right.....someone correct me if I'm wrong.

 

Well the change was halfway through 87. You can check on Mazdatrix.com and get the VIN cutoff. I guess the 87.5+ don't have the resistor pack, right? I forgot if mine even has one now that I think about it. Haven't messed with it in a long *** time.

 

well i have the resistor pack and high impedance injectors (if high impedence are the ones with 12+ ohms resistence.. thats what i have)

 

how do i get to the ecu? what screws do i gotta pull to get the carpet up?

 

If you have the resistor pack then the injectors you want to use have a notch in the middle of the little orange piece that connects to the harness. The high impedance injectors have the notch off to the side. Make sure that if you have the resistor pack ALL of your injectors have the notch directly in the middle.