Hey folks, sorry I can't search I have limited time on the internet.

Just a quick question. I am doing a swap right now. S5 motor bone stock that is going into an S4. Entire drivetrain is being swapped also. Will I run into any electrical problems at all???

Only real thing I am concerned about. Also would swapping out the FPD be a smart thing to do, or was that only a problem on the S4. I already know about the shitty plastic coolant filler neck, wtf was mazda thinking?



Thanks
Justin

 

Yeah, you will run into electrical problems.

Nothing will match up. The S4 ECU won't work and a S5 ECU won't either.

Wrong series.

You'll have to make a custom harness or change the wiring to match up.

 

I already have everything needed for the swap. everything for the s5 and I mean everything! s5 ecu, wiring harness, entire drivetrain, motor, mounts, etc.

only thing that is going to be s4 is the car itself.

so maybe I would be better off doing aftermarket ecu like haltech or microtech?