A portable power impact wrench with a unique feature is disclosed. The wrench contains an actuator, which when activated, usually by a trigger, gives an automatic and predetermined amount of torque to the wrench. The torque is just sufficient to break the initial tightness of a nut. The wrench has utility, for example, for loosening a tire wheel lug nut which has been highly torqued by garage automatic impact wrench. The wrench also has industrial utility.