Hi, I have a Mazda Protege 2002 DX with the manual transmission. I have a repeating P0303 engine code, cylinder 3 misfire. I have gotten new spark plugs, new coil packs and wires, and new fuel injectors. When I got new fuel injectors the problem disappeared for about a week, and now it is back after installing a short ram air intake. I also have seen code P0300, P0171, and P0106 come on after driving awhile. I have cleaned my EGR valve, and have ordered a new MAF sensor, but have yet to install it. Any ideas? Do I have some engine damage because I ran for a couple of days without new fuel injectors on cylinder 3? Thank you.