The "tuner tube" is a small plastic tube that is installed in some engines to tune and quieten the intake noise.
The tuner tube can be found in the intake system of the following J-body engines:
96-02 2.4L Twin Cam (LD9)
98-02 2200 OHV (LN2)
The tuner tube is slid into the black plastic air intake resonator on top of the throttle body. If you remove the flexible rubber intake piping, you should be able to spot the edge of the tuner tube. Using a flat-head screwdriver, you can pry the lip of the tube outwards, so that you can remove the tube.
Removing the tuner tube will not provide great gains in HP... but will slighly increase airflow and sound a little beefier.
Removing the intake resonator (the black box on top of the throttle body) and replacing the entire stock intake system, right to the throttle body, is a much better alternative!
