[FC TII S4] What is this ?
 

Hi !

As you can see here: https://www.rx7club.com/introduce-yourself-254/hi-switzerland-952705/ I made one FC with two. Both are S4.

I changed the engine because the first was having troubles. But after I changed it, there was this :

http://i21.servimg.com/u/f21/14/31/47/32/dsc00110.jpg

With the first engine, it was plugged in, and now I can't find where to plug it in...

Do you have any idea of what it is ?? the engine works but... I don't know if it's important.

(sry for my english)


Thanks !

Jrm1005

That is the resistor pack (four 6 ohm resistors) for the fuel injector circuits. Did you switch out the emissions (EM) harness along with the engine? '87.5 to '88 S4s did not use this pack, and instead had high impedance injectors (12-13 ohm), but early S4s ('86 to '87.5) used low impedance injectors (2-3 ohm) & this pack of resistors.

You need to figure out if your injectors are low or high impedance. The easiest way is if you check the tab on the plug. If it is centered, it's a low impedance injector. If it is offset to one side, it is high impedance.

the resistor pack is for s4(injectors)..and it looks like the other thing in that pic is S5 fuel pump realy and resistor pack?..
I could be wrong.

Thanks for your answers :-)

Well I thought that both engine were the same. But it seems like no now... What are the EM ?

I changed the complete engine (in one block, but I didn't change the ECU (I will do it, I think it's better now that I know there are differences)) , the fuel pump and the exhaust. Should I change something else ?

The ECUs should be the same. The EM harness is the primary wiring harness that connects to all of the engine sensors and the ECU. You really just need to find out what injectors you have in there. If they're high impedance, you don't need to change a thing. If they're low impedance, you can either swap the other harness in, or wire aftermarket resistors in-line.