I (we) cannot get at the manual. can you copy it into a post?
see if the manual lists the wire going to the fuel injectors, then put the relay into that wire. thats what I did as most newer cars have several things on the same fuse that runs the injectors. Things like fuel pump (you can burn it out with over cycling) so try to find the wires to the injectors. there might be one in the fuse panel. my bothers kia had a separate one but my matrix did not.
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