The other day I cut off my back muffler. Right before the back muffler there is another piece to the exhaust, I believe it to be a resonator, but it could be another muffler. My question, what is it? And if I cut it off will it throw a cell?
It will not through a SES. (Service Engine Soon) light. I don't know about the stadard Focus, but on the SVT Focus, thier is a tunned muffler, muffler, resonator, and cat. As long as your cat is on, it will not through a code.
No, you shouldn't have any problems with the car throwing the CEL (check engine light). I am currently running a 4-1 race header, no cat, and Magnaflow catback and I have never gotten a CEL. NO MIL eliminator either.