My '02 F-150 4.6L with 211k miles on it started missing real bad the other day. I changed the fuel filter, removed and cleaned the throttle body, egr ports and IAC valve and changed the pcv valve. Now it has a little miss at idle but the real problem is when I get into the gas hard, it misses and stutters bad! Any idea what that could be? I also cleaned the MAF sensor and air filter.