hello all,

before questions here is my configuration:
s5 turbo 13b
ms3/ms3x
stock 550's
stock ignition
fd tps & iac

im trying to plan out all my wiring for my ms3 w/ms3x. i have a few questions.

1. when wiring the fuel injectors should i use the outputs on the ms3 connector or ms3x? and if i do the ms3x do i wire them individually or in waste fire config?

2. should i add in a shielded wire to the ms3x harness for the 2nd vr input?

3. do i have to put a diode in the pwn iac valve like aaron did in his write up?

ill have more questions later im sure. thanks for any help!

 

MS3X, and each injector is wired individually.

DIYAutoTune has good documentation on this.

Yes. The wire provided in the stock harness from DIY (and like others) is unshielded.

Yes. Anytime you are switching any kind of relay or inductive load.

 

thanks Aaron!

when wiring my 2nd vr input the ms3x wiring schematic says "to ground connection on main db37 plug" for the ground side of it. which ground connection should i use? can i just use the same ground that the main vr uses?

 

Any of the grounds on the top of the MS3X DB37 will do. No, don't tie the VR grounds together. The VR circuits work best when their sensor ground is as close to them as possible.

 

should i have it ground through the shielded wire?

 

If you look at the DIY autotune main harness it has a 2 conductor shielded cable, so I also ran the same thing on the MS3x harness for the cam input and ground.

 

thanks^ i re did mine the same way.

next question, do i need to use a external diode on the fan relay switch wire if the documentation says "The MS3X 'PWM' outputs are internally protected against 'flyback' from relay coils. " im guessing not, but if its a good idea i will still add it in for redundant protection.

 

You don't strictly need the diode at the relay in that case, no.