This TSB applies to 2011 Mazda2 vehicles with DTC P0451:00 (fuel tank pressure sensor range/performance problem). This may be caused by water or snow entering and freezing in the atmosphere breather hose of the fuel tank pressure sensor (FTP).
Verify the concern.
Remove the L-shaped atmosphere breather hose from the FTP sensor and inspect for water and/or ice. If water is found, drain water from the FTP sensor by shaking it. If ice is found, warm up the sensor and drain. DO NOT use pressurized air to drain water from the FTP sensor ro avoid sensor damage.
Cut a new hose to 160 mm in length (original hose length is approximately 999 mm).
Peel off and discard the tape on No. 4 cross member. Apply rust preventative paint where the tape was removed, then install a new clip.
Remove and discard the original L-shaped breather hose from the FTP sensor.
Attach the new 160 mm-long hose to the FTP sensor, the attach the other end of the hose to the new clip. Using M-MDS, confirm FTP sensor PID voltage reading is within 2.5 – 3.6 volts, then perform an evap self test. If the FTP sensor voltage reading is within range and the self test passes, proceed to the next step. If FTP sensor voltage reading is out of range and the self test fails, replace the FTP sensor.
Clear the stored DTC in the PCM and verify the repair.
New hose (cut to 160mm)…...9935-10-4999