I changed my IMRC, on my 05 screw 5.4, last spring and ever since its had a couple of little problems, but I'm not sure if its related. I have some detonation under light load, and almost like a slight dead spot in the 1500-2000 rpm range. And seems like over all low power compared to other similar trucks.

I was told that I had to remove the intake to change the IMRC, but being the stuborn guy that I am, I changed it without removing it. It wasn't easy but with my small hands and a good mirror I got it in there and the engine light went out, so I figured it was good, but know I'm thinking that it may be related to my other problems as the seemed to happen at around the same time. Could these symtoms be caused by the IMRC or would the engine light come on if it wasn't right?
Can the IMRC be monitered on a good scan tool to see if its functioning properly?
Thanks