heres the story, i just bought an a-spec harness for my s4 t2 and for some reason the fin american spec harness has different plugs for the injectors and now my injectors wont fit properly into the scocket. i couldnt find anything on the fourm saying there are different types of harness ( besides 24 and s5). can anyone shed some light on my issue? is there a way to tell the difference if the guy sent me an s5 harness? or are the jpec injectors different from the american spec?

 

the shape (and color) of the injector plugs signify what year, size, and impedance the injectors are. There are charts on here if you search a bit, and before you go just plugging them in, make sure that the harness and injectors match impedance (and if they're low-imp, that you have the resistor pack hooked up)

 

series 5 harnesses have oval shaped injector plugs for high impedence injectors, s4's have square shaped, 88s have high imp. while 87's had low imp.

 

Let me clarify all this.

Its really simple:

86-87 rectangle on center plugs for low impedance injectors
87-88 rectangle off center plugs for high impedance injectors
89-91 oval plugs for high impedance injectors.

TAN/PURPLE injector = Low impedance
RED/ORANGE injector = High impedance injector

Harness and injectors must match otherwise....no go or big damage.

 

Solenoid resistor - if present (i.e. you have low impedance injectors), you'll find it mounted to the body under the stock air filter housing. It has a plug (roughly oval shaped) with five wires.

 

well i appriciate the help with that clairfaction on different impedence injectors but this is not the case. i knew that the injector plugs on an s5 and s4 were different (one being round and one being square) but that not be my issue. the issue is that on the SQUARE injector plug there is a guide for the injector, and on the injector there is a male end for the guide, the problome now is that the male end and the guides are in the wrong place for all the injectors. and other ideas? any help is appricated.

 

if both the harness and injectors match impedances, who cares if the guide matches up? shave it off with an x-acto knife and go. I had to do this with aftermarket injectors, the purpose of the guide is to make sure that you dont go plugging low imp injectors into a high-imp harness and burn them up. If you are SURE that you have the right imp injectors and harness, just trim the plugs to fit.

 

Is this guide on the injector plugs the same between primary and secondary injectors? Don't have any in front of me...

 

Your problem is as stated above. You have the wrong harness for the car. Either your injectors are high imp and the harness is low, or vice versa.

 

The offset notch it to prevent the use of the wrong impedance injector.
S4's had two impedances dependant on year.
AT first is was Low impedance(resistor pack placed near the air filter)
Then 87.5-88 had high impedance.

What impedance ones are you using?

It's easy to get around this.

Just remove the resistors if you want to use high impedance injectors on a low impedance harness.

Or add resistors inline of you want to use low impedance

To get around the notch. I just used a razorblade to cut it down on the injector enough to slide in.

 

Not necessarly. You can have low impedance with or without the resistor pack.

Ask me how I know.

 

Dude, read carefully what I posted.

 

oh alright. i see now. well this kinda sucks... any one have any idea's? am i able to jsut switch the injectors or will there be an issue with the ecu? do i need to just get another harness?

 

scratch that very last post. the real question now is how to trouble shoot this. from what it looks like i have low impedence injectors with a high impedence harness. Digi7ech kindly stated that all i would have to do is put resistors in. if i were to put the resistors in were would they splice into the harness ? all this is very helpfull and i really appricate your guy's advice. would anyone happen to have pictures on hand or a link of such site to further assist me? thanks!

 

This is all going to depend on what type of ECU you have, versus what type of injectors you have.

You could have high impedance injectors on a low impedance harness, or vice versa. What I need is the number off the side of the injectors.

 

Can't you just put High impedence Injectors in and forget about the resistor pack? I think I asked NZ convert about this before and he said you could.

 

if you have low imp injectors driven thru the high imp harness, as soon as you hit high duty cycles, you'll burn either them or your ecu out. Idling and light cruising you may be ok

 

Get high impedance injectors.

 

Getting all new injectors is pointless when it could be as simple as a few wires soldered and possible 4 6.8 Ohm x 10watt resistors.