i'm looking at my S4 UIM and my SE UIM side by side, and they appear identical right down to the harness connector, with the only visible difference being how they're mounted.

so my question is can i use a S4 TPS with an S3 ECU? it looks like it'll be easy to adapt the mounting bracket from the S3 TPS to fit onto the S4 TB, but if the the s4 part will work with my se computer, i may as well save the effort.

 

Yes, the S4 TPS should work just fine. You can check the resistance to be sure, but I am pretty sure that the S4 TPS resistance ranges from 1k-5k like the -SE one does.