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[alpalwal]

I recently put in a z32 maf, 900cc injectors, and a new ECU in my 240sx (KA-T)

I had to change everything at the same time because they can't work alone. The ECU is tuned for the setup but I'm running extremely rich. I'm showing about 8:1 at idle and it doesn't move too much from there. It's running pretty rough as well.

I was thinking that maybe I have the wrong impedance injectors. Could that be my issue?
Also, on the off/unfortunate chance that I have the injector wires going to the wrong injectors, how could I check to make sure they're firing on the right ones? My wires aren't labeled and I'm not sure where to look from here.

[t_cel_t]

i think if you use high impedance on a low impedance it will eventually wreck the ecu because its drawing way too much current to run the injectors.
also i don't think firing order has any effect, im pretty sure most vehicles actually fire half the injectors at the same time.

[AstroVannin]

I had low impedence injectors in my Tercel (normally high impedence) with NO issues.

[alpalwal]

Alright, I just took a look online and it seems that they're normally high impedance. Any easy way to check the impedance of an injector?

I think the injector firing order has some effect because I switched the wires on 2 and 3 and it ran even shittier.

[Conceptz-X]

Resistance  Check them against your old injectors, Low resistance = Low Impedance

[alpalwal]

I don't have the old injectors any more. Can someone take a quick resistance measurement of a known high or low injector please?

[Conceptz-X]

What is the resistance of the ones you have?

[Conceptz-X]

Typical:
High impedance resistance injectors (12 - 16 ohms)
Low impedance resistance injectors (2 - 5 ohms)

[alpalwal]

Alright, now I'm just confused. I pulled the injector wire off and put the two contacts from the multimeter on the 2 different leads on the injector.

I put it on ohms and tried it at 10,100,1000. On all 3 settings the meter was basically pinned to the right (barely any resistance at all).
I tried it on 2 injectors with the same results.

what am I doing wrong?

[Conceptz-X]

may be shorted 

Or your meter is crap.  Try a digital meter if you can borrow one

[alpalwal]

Is that an injector problem or an ecu problem?

[Conceptz-X]

Injector if its shorted. 

You should have one lead to the injector that is battery voltage, and the other should pulse ground.  get a Noid light or use a test light to check it.

[alpalwal]

Alright, now I'm confused. I found another pair of injectors to measure the resistance on and when I put the multimeter on the two leads of the injector it showed open circuit as well. So, unless I have 6 randomly shorted injectors I think I'm doing something wrong.

[Adam Hopkins]

Do you have the terminals plugged in the right spot on your volt meter. Some meters have three holes. You need to make sure one of the wires is plugged into the terminal with the omega symbol.

[alpalwal]

Alright. I think I've figured out that they're low impedance injectors. Even though astrovannin said that that worked fine on his tercel I think I'm going to wire in some resistors anyways because I'm not sure where else to start.

What kind of resistors do I need?

[alpalwal]

Alright, figured out the resistors I need and I picked them up.

one last question, which wire do the resistors go on? + or -?

[BoostForLife]

Alright, figured out the resistors I need and I picked them up.

one last question, which wire do the resistors go on? + or -?

the common power wire.

Just google a resistor box install. Concept should be the same.