Each cylinder has two sets of runners, one for low speed and rpm is when just one of the runners is open, but ; when you command the engien for more power the second one will open to supply you with more air.
IMRC monitor signal circuit shorted to PWR GND or SIG RTN.
Damaged IMRC actuator or solenoid.
Blocked vacuum hoses.
Those are the possible causes, I suggest you take it in.