s4/s5 ecu
 

Is it possible to run a s4 n/a engine in a s5 chassis? Can I use s5 ecu and harness?? How can I make this work?? Thanks

yes/yes/search

IIRC
s5 harness will be used for the engine
where the harness connects to the body in the passenger footwell you'll have to modify it and use the s4 plugs.

Ive been researching like crazy. Currently the car runs on s5 harness and ecu. But can only take so much throttle before it cuts out. We r using s5 injectors and s5 afm. At first car didn't start with s5 tps. Swapped tps with s4 and it started and idled fine. But couldn't drive. then swapped back to s4 afm and runs little better. But s5 harness for afm is only 5 pin. S4 afm is 7. So I matched wires and left 2 off that didn't match. So that could be a problem. It will drive but cannot accelerate or stomp gas, it Jus cuts out.

You can't just mix and match electronics between series. S4 and S5 ECUs/sensors/wiring are very different. You need to keep everything from the same series. The simplest way to go is to not change the ECU/sensors/wiring from S5, and just use the S4 engine as a short block. Bolt on all the S5 peripherals you can, including the S5 front cover and OMP. If you use an S5 ECU without an S5 electronic OMP plugged in, it will go into limp mode.

Ok, ill try that. Thanks alot.