96 Tbird 4.6L. Well maintained. Ran great bit suddenly wouldn't start the next morning. Fuel pump primes (replaced fuel filter just in case), has spark, clean MAF and throttle body/plenum, intake aor temp sensor reading good voltage, coolant temperature sensor read 5V (replaced). Car starts with pedal floored. Idles up to 1800 before it feels smooth. Pull MAF connector and idle drops slightly. Pull IAC connector (on my third one in 10yrs), car dies. Ideas?