A method, a control unit, and a computer program for detecting a defective intake-manifold pressure sensor andor a defective ambient-pressure sensor in an internal combustion engine having a variable valve timing are provided. The coupler includes a tool collet and an attachment locking mechanism operable to permit tool collet operation and telescoping movement of an attachment tube with respect to the dissection tool. Such new warp sizing and fixing agent is suitable to be used in fully continuous dyeing processes, if desired in combination with additional sizing additives. The surface of the recess is sealed and coated with a release agent.