An apparatus for in-line re-calibration of engine load signal, the apparatus having a housing and a first connector disposed on the housing, adapted to plug into an electrical connection socket of an automotive air intake sensor. A second connector is disposed on the housing, adapted to mimic the electrical connection socket of the automotive air intake sensor. An electronic circuit is disposed in the housing, the electronic circuit adapted to re-calibrate signals from the automotive air intake sensor and deliver the re-calibrated signals the to the second connector. The housing is adapted to plug in-line directly into the electrical connection socket of the automotive air intake sensor, whereby the corresponding electrical wiring connector to an engine control unit plugs directly into the second connector of the housing, completing the inline connection.