RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   S4 N/A two different flavors of injector - WTF? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s4-n-two-different-flavors-injector-wtf-716265/)

throughthewire 12-27-07 08:24 PM

S4 N/A two different flavors of injector - WTF?
 
I just bought an S4 N/A engine that I'm going to tear down and rebuild for my 88 Vert.

I yanked the injectors and was getting ready to send them to Witchhunter, and noticed that even though they're all labeled 195500-1350, one pair has a slightly different appearance.

So I measured them, and sure enough, one set measured 2.3 Ω and the other measured 12.9 Ω. :Wconfused

There's no way that it came like that, did it? Wouldn't that seriously confuse the ECU? :scratch:

NZConvertible 12-27-07 08:33 PM

Unless there are some resistors somewhere for those low-impedance injectors, you're lucky they didn't fry the ECU's injector drivers.

If you can't find any resistors, measure the resistance from all four injector clips to the respective pin on the ECU connector to see if they're there. If two of the wires measure ~10ohm then you're sweet (make sure the low-imp injectors go back on those clips). If they measure near zero then you need to add 10ohm, 10W resistors to the wires that go to the low-imp injectors, or replace the low-imp injectors with high-imp injectors.

throughthewire 12-27-07 08:45 PM


Originally Posted by NZConvertible (Post 7670596)
Unless there are some resistors somewhere for those low-impedance injectors, you're lucky they didn't fry the ECU's injector drivers.

Thankfully, it's not in my car yet—I have a running engine now, I'm just building a second one since my daily-driven Vert just passed the 135,000 mile mark.

I imagine the car it came out of didn't run so well, though!


If you can't find any resistors, measure the resistance from all four injector clips to the respective pin on the ECU connector to see if they're there. If two of the wires measure ~10ohm then you're sweet (make sure the low-imp injectors go back on those clips). If they measure near zero then you need to add 10ohm, 10W resistors to the wires that go to the low-imp injectors, or replace the low-imp injectors with high-imp injectors.
Thanks! I'm going to measure all the connectors on my car tomorrow, and replace whichever set of injectors is a mismatch for my current harness/ECU.

Gawd I hate finding weird crap. :wallbash:

NZConvertible 12-27-07 09:35 PM

Oops, sorry. I didn't click to the fact that the engine had never been in the car. ;)

Don't bother measuring your car, I'm sure it'll have four matched injectors. You'll need to do something with those low-imp injectors in the new engine though.


All times are GMT -5. The time now is 08:11 AM.


© 2024 MH Sub I, LLC dba Internet Brands