RXntrik7

So I'm very close to getting my TII swap running, the problem is my injectors are not operating. I'm getting fuel to the rails and I'm getting spark however car won't start.

I'm using low impedance injectors so I wired in resistors on the four wires coming out of ECU. According to me this should have been simple, but obviously I'm not too clear how the rx-7 wiring is done. Especially since I noticed that factory resistor pack only has 5 wires going to it. I'm not sure how this works. A diagram or a schematic would be nice. Or if anyone has a decent explanation I'll take that too.
Anyway I tested the voltage on the primary injector wire where I soldered in the resistor with a test light and I got current, but I also heard injector click at the same time. right after I tried starting the engine and it run on one rotor for a second. So I'm assuming I opened the injector when I tested for current. Now I made a simple schematic showing how I probably screwed something up. Please help me determine the problem and also could someone explain how the 5 wire resistor pack works.

satch

iTrader: (1)

Here's the diagram
https://www.rx7club.com/attachments/...lackyellow-jpg

Notice that the Green wires run from the ECU to the injectors and these are the wires you placed inline w/the new resistors. Also, notice the Brown wires that run to each injector. These wires provides the power to each injector. So, the Brown wires woild all be fused together and connected to the Black/Yellow wire in the diagram that comes from the Main Relay and has voltage w/key to start and on positions.

The wire colors from the ECU and feed wires (those w/voltage) would be a different color than yours.

RXntrik7

Sorry I forgot to mention the colors of the wires I drew on the pic don't represent actual wire colors on the car but that should be obvious.

Thank you that diagram explained pretty much everything. So since I spliced in the resistors on the other side of injectors does this explain why they are not working? Have I damaged the ecu by doing so?

satch

iTrader: (1)

It actually does not matter which side the resistors are located. Are you sure the EGI INJ fuse is good (found on S4's) If it were then the Black/Yellow wire would have voltage w/key to on at the injectors. Also, the primary injectors are the only ones that would work when starting, idling, driving the car w/o load and below 3800 rpm, thus the secondary injectors would not work under these three conditions. Are you checking the primaries or secondaries is basically what I'm pointing at.

RXntrik7

Yes I made sure to test primaries
When I touched the 1 primary injector wire at the ecu (the light green) with a test light I heard a click. I guess that means when I applied the negative to the green wire injector activated. Which means I am getting current from the main relay. I'm not sure what else to check.
Why does it matter where resistors are placed? But if it does then I'll have to dig into the harness under the hood.

satch

iTrader: (1)

I said "it does not matter." And how do you know they are not working? Is it just because the car is not working?If you have a spare CAS you can connect it to the harness and w/key to on spin the CAS wheel and the primary injectors will click. You might want to disconnect the plugs that supplies voltage to the coils as they will also make a sound which might drown out the sound of the injector clicks. You could also use the CAS in the car but you'll have to restab it.

RXntrik7

Well problem solved. Actually it wasn't what I was expecting at all. Turns out the injectors were seized up. I performed a test using another CAS and wasn't getting any injector activity. Then all of the sudden one started clicking. I took the UIM off, tapped the other primary with a screwdriver and it started working. I never would have thought and I was ready to contact digital tuning to suggest to them that ECU is faulty after Rtek upgrade or something. Thanks for your help satch.