They had to switch them out.. Look at what ecu is in the car first. You will not be able to run any of those 3 ecu's with those injectors if you do not modify the silenoid resistor.. Is there a mechanical Oil metering pump or an electric one on the front?? And does your Throttle body have 1 or 2 TPS's? I'm betting on you having anothe s4 ecu in the kicker panel. To be able to run a s5 ecu in an s4 car you have to do some serious body harness modding which is a complete waste of time for the same power. Heres what you need.

Make sure you modify your resistor for the higher IMP injectors (cutting and splicing a couple wires). Use an S4 (single TPS) throttle body (I have one if you need it). A mechanical OilMeteringPump (I have one with the bar linkage)You might have to swap to an s4 front cover, or just run premix. An S4 AFM NOT a round S5 MAF. And one of your n326 ecus. All that stuff should have it running how it's suppose to. The car will run like ass or not at all if you do not have the appropriate electronics for the ecu you are running. And since it is an s4 car (body harness) you won't be able to run an s5 ecu or s5 electronic (OMP, MAF) Rx7club.com has every single one of these issues covered 10x over, you just have to sign up and search.