The Bosch LSU4.2 wide-band O2 sensor (shipped as part of the LM-1 kit) is rated to operate at an exhaust gas temperature of < 1300 degrees (F), and a sensor housing temperature of < 900 degrees (measured at the bung) for maximum accuracy and control. When either of these operating temperature ranges is exceeded, the sensor can no longer be accurately controlled. Further, operating at or over these temperatures for any length of time can significantly reduce the lifetime of the sensor. The LM-1 is designed to display an error message under these conditions (currently 08- Sensor Timing Error) rather than provide inaccurate readings. For some turbo vehicles, rotary engines, and other setups, this error message can be encountered with annoying frequency.
The HBX-1 is intended to provide a
degree of thermal isolation in applications
where the pipe temperature
exceeds 900°F (approx. 500°C) with a
heat-sinking design intended to screw
into a new or existing 18mm bung.