Surging???????????????

Have you changed anything lately? Mine started surging after I changed the plugs. I'm guessing that some of those hard to reach ones may have closed up a bit. Also have you removed or changed your Mass Air stuff recently? Maybe while cleaning the air filter? That's another thought I have for mine. I removed all that to get to the plugs. Maybe I didn't put it back right??? Not sure, but hope to find out soon!