What episode is it when peter calls from the kitchen saying hes at office and cant take out trash?

The episode you are referring to is "Petarded", the second episode of the sixth season of Family Guy. In this episode, Peter pretends to be at the office while at home to avoid taking out the trash. He calls Lois from the kitchen, pretending to speak to his boss Mr. Weed on the phone; Peter speaks in a high-pitched tone and tries to make excuses until Lois becomes convinced and hangs up. Upon discovering Peter's ruse, Lois is furious and threatens to leave him