i was just wondering how to find out if the motor is an S5 or an S4, is there something to look at to find out what it really is...

 

the AFM is a good indicator......S4's have a large silver "square looking" one, where as an S5 has a round tubular black one.

On an N/A the UIM is also a good indicator.

Also, there will be 2 TPS's on an S5, only one on an S4

 

This is covered in the FAQ.

 

would knowing it also matter by the ecu because i got the motor and it came with the N374 ecu and i think that is a S5 ecu but just not sure if its an s5 motor or an s5..