you should just check under your front bumper to make sure the whole plastic covering is securely attached. half of mine was falling off and was letting in a ton of air from the underside, and it completely threw off the maf reading. whenever i clutched on the highway, my engine constantly stalled, esp. on deceleration. basically whenever i let go of the gas and put the car in neutral while coasting, the z would stall. after the fix, its dead steady... hasn't stalled since =) you definitely should check.
