I just bought a Honda Fit with dealer installed Mugen sport pedals. Is the accelerator pedal suppose to be a little bit loose. I don't think it suppose to but I wanted to know other peoples experience before I call up the dealer.

 

Its most likely the rivets that were used. They're supposed to break off once the outer sleeve is spread enough, but they don't always do that, sometimes breaking a hair too early.

I say, get a wooden block with a small steel plate on it, put a nail puncher with a wide head on top, pointing at the rivet... then a second nail puncher and hammer the other end. Basically pounding the rivet until its tightened against the pedal.