Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:13:p4
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 13 (pt 4/23)
Character Range: 1952648–1955999

may monitor the front catalyst alone or in combination with the next catalyst(s) downstream. Each monitored catalyst or catalyst combination shall be considered malfunctioning when the emissions exceed the NMHC or NOx OBD thresholds set out in paragraph 6.8.2. of this Regulation.

              3.3.3.2. The presence of engine misfire in the engine operating region bounded by the following lines:

                  (a) A maximum speed of 4,500 min-1 or 1,000 min-1 greater than the highest speed occurring during a Type 1 Test cycle, whichever is the lower;

                  (b) The positive torque line (i.e. engine load with the transmission in neutral);

                  (c) A line joining the following engine operating points: the positive torque line at 3,000 min-1 and a point on the maximum speed line defined in (a) above with the engine's manifold vacuum at 13.33 kPa lower than that at the positive torque line.

              3.3.3.2.1. Specific monitoring rate for misfire:

              For Level 1B only

                  (a)  Catalytic converter protection. The engine misfire which causes the catalytic converter damage because of excessive heat, shall be monitored every 200 revolutions within the region specified in paragraph 3.3.3.2.

                  When the evaluated engine misfire rate is less than 5%, the limit can be fixed at 5%.

                  (b)  Exceeding emission threshold. The engine misfire which causes to exceed an emission threshold shall be monitored every 1,000 revolutions within the region specified in paragraph 3.3.3.2.

                  When the evaluated engine misfire rate is less than 1%, the limit can be fixed at 1%.

              3.3.3.3. Oxygen sensor deterioration

               This paragraph shall mean that the deterioration of all oxygen sensors fitted and used for monitoring malfunctions of the catalytic converter according to the requirements of this annex shall be monitored.

              3.3.3.4. Other emission control system components or systems, or emission related powertrain components or systems which are connected to a computer, if active on the selected fuel, the failure of which may result in tailpipe emissions exceeding any of the OBD thresholds set out in Table 4A and Table 4B (as applicable) in paragraph 6.8.2. of this Regulation.

               The following is a non-exhaustive list providing examples of representative components and systems:

           (a) Exhaust gas recirculation system

           (b) Fuel system

           (c) Secondary air system

           (d) Valve timing system

           (e) Atmosphere pressure sensor

           (f) Intake air pressure sensor

           (g) Intake air temperature sensor

           (h) Air flow sensor

           (i) Engine coolant temperature sensor

           (j) Throttle sensor

           (k) Cylinder identification sensor

           (l) Crank angle sensor

              3.3.3.5. Unless otherwise monitored, any other emission-related powertrain component connected to a computer, including any relevant sensors to enable monitoring functions to be carried out, shall be monitored for circuit continuity.

              3.3.3.6. The electronic evaporative emission purge control shall, at a minimum, be monitored for circuit continuity.

              3.3.3.7. Only for Level 1A