Section 86.004-25 includes text that specifies requirements that differ from §86.094-25. Where a paragraph in §86.094-25 is applicable to §86.004-25, this may be indicated by specifying the corresponding paragraph and the statement “[Reserved]. For guidance see §86.094-25.”.

(a)

(1) Applicability. This section applies to light-duty vehicles, light-duty trucks, and HDEs.

(2) Maintenance performed on vehicles, engines, subsystems, or components used to determine exhaust, evaporative or refueling emission deterioration factors, as appropriate, is classified as either emission-related or non-emission-related and each of these can be classified as either scheduled or unscheduled. Further, some emission-related maintenance is also classified as critical emission-related maintenance.

(b) Introductory text through (b)(3)(ii) [Reserved]. For guidance see §86.094-25.

(b)

(3)

(iii) For otto-cycle heavy-duty engines, the adjustment, cleaning, repair, or replacement of the items listed in paragraphs (b)(3)(iii) (A)-(E) of this section shall occur at 50,000 miles (or 1,500 hours) of use and at 50,000-mile (or 1,500-hour) intervals thereafter.

(A) Crankcase ventilation valves and filters.

(B) Emission-related hoses and tubes.

(C) Ignition wires.

(D) Idle mixture.

(E) Exhaust gas recirculation system related filters and coolers.

(iv) For otto-cycle light-duty vehicles, light-duty trucks and otto-cycle heavy-duty engines, the adjustment, cleaning, repair, or replacement of the oxygen sensor shall occur at 80,000 miles (or 2,400 hours) of use and at 80,000-mile (or 2,400-hour) intervals thereafter.

(v) For otto-cycle heavy-duty engines, the adjustment, cleaning, repair, or replacement of the items listed in paragraphs (b)(3)(v) (A)-(H) of this section shall occur at 100,000 miles (or 3,000 hours) of use and at 100,000-mile (or 3,000-hour) intervals thereafter.

(A) Catalytic converter.

(B) Air injection system components.

(C) Fuel injectors.

(D) Electronic engine control unit and its associated sensors (except oxygen sensor) and actuators.

(E) Evaporative emission canister.

(F) Turbochargers.

(G) Carburetors.

(H) Exhaust gas recirculation system (including all related control valves and tubing) except as otherwise provided in paragraph (b)(3)(iii)(E) of this section.

(4) For diesel-cycle heavy-duty engines, emission-related maintenance in addition to or at shorter intervals than the following specified values will not be accepted as technologically necessary, except as provided in paragraph (b)(7) of this section:

(i) For diesel-cycle heavy-duty engines, the adjustment, cleaning, repair, or replacement of the following items shall occur at 50,000 miles (or 1,500 hours) of use and at 50,000-mile (or 1,500-hour) intervals thereafter:

(A) Exhaust gas recirculation system related filters and coolers.

(B) Crankcase ventilation valves and filters.

(C) Fuel injector tips (cleaning only).

(D) DEF filters.

(ii) [Reserved]

(iii) The adjustment, cleaning, repair, or replacement of items listed in paragraphs (b)(4)(iii) (A)-(G) of this section shall occur at 100,000 miles (or 3,000 hours) of use and at 100,000-mile (or 3,000-hour) intervals thereafter for light heavy-duty diesel engines, or, at 150,000 miles (or 4,500 hours) intervals thereafter for medium and heavy heavy-duty diesel engines.

(A) Fuel injectors.

(B) Turbocharger.

(C) Electronic engine control unit and its associated sensors and actuators.

(D) Particulate trap or trap oxidizer systems including related components (adjustment and cleaning only for filter element, replacement of the filter element is not allowed during the useful life).

(E) Exhaust gas recirculation system (including all related control valves and tubing) except as otherwise provided in paragraph (b)(4)(i)(A) of this section.

(F) Catalytic converter (adjustment and cleaning only for catalyst beds, replacement of the bed is not allowed during the useful life).

(G) Any other add-on emissions-related component (i.e., a component whose sole or primary purpose is to reduce emissions or whose failure will significantly degrade emissions control and whose function is not integral to the design and performance of the engine.)

(iv) [Reserved]

(v) For engines that use selective catalytic reduction, the diesel exhaust fluid (DEF) tank must be sized so that DEF replenishment can occur at an interval, in miles or hours of vehicle operation, that is no less than the miles or hours of vehicle operation corresponding to the vehicle's fuel capacity. Use good engineering judgment to ensure that you meet this requirement for worst-case operation. For example, if the highest rate of DEF consumption (relative to fuel consumption) will occur under highway driving conditions (characterized by the SET), the DEF tank should be large enough that a single tankful of DEF would be enough to continue proper operation of the SCR system for the expected highway driving range with a single tank of fuel. Conversely, if the highest rate of DEF consumption (relative to fuel consumption) will occur under city or urban driving conditions (characterized by the transient FTP test), the DEF tank should be large enough that a single tank of DEF would be enough to continue proper operation of the SCR system for the expected city driving range with a single tank of fuel. For engine testing in a laboratory, any size DEF tank and fuel tank may be used; however, for our testing of engines, we may require you to provide us with a production-type DEF tank, including any associated sensors.

(5) [Reserved]

(6)

(i) The following components are defined as critical emission-related components:

(A) Catalytic converter.

(B) Air injection system components.

(C) Electronic engine control unit and its associated sensors (including oxygen sensor if installed) and actuators.

(D) Exhaust gas recirculation system (including all related filters, coolers, control valves, and tubing).

(E) Crankcase ventilation valves and filters.

(F) Evaporative and refueling emission control system components (excluding canister air filter).

(G) Particulate trap or trap-oxidizer system.

(H) Components comprising the selective catalytic reduction system (including DEF tank).

(I) Any other component whose primary purpose is to reduce emissions or whose failure would commonly increase emissions of any regulated pollutant without significantly degrading engine performance.

(ii) All critical emission-related scheduled maintenance must have a reasonable likelihood of being performed in-use. The manufacturer shall be required to show the reasonable likelihood of such maintenance being performed in-use, and such showing shall be made prior to the performance of the maintenance on the durability data engine. Critical emission-related scheduled maintenance items which satisfy one of the conditions defined in paragraphs (b)(6)(ii) (A)-(F) of this section will be accepted as having a reasonable likelihood of the maintenance item being performed in-use, except that DEF replenishment must satisfy paragraph (b)(6)(ii)(A) or (F) of this section to be accepted as having a reasonable likelihood of the maintenance item being performed in-use.

(A) Data are presented which establish for the Administrator a connection between emissions and vehicle performance such that as emissions increase due to lack of maintenance, vehicle performance will simultaneously deteriorate to a point unacceptable for typical driving.

(B) Survey data are submitted which adequately demonstrate to the Administrator that, at an 80 percent confidence level, 80 percent of such engines already have this critical maintenance item performed in-use at the recommended interval(s).

(C) A clearly displayed visible signal system approved by the Administrator is installed to alert the vehicle driver that maintenance is due. A signal bearing the message “maintenance needed” or “check engine”, or a similar message approved by the Administrator, shall be actuated at the appropriate mileage point or by component failure. This signal must be continuous while the engine is in operation and not be easily eliminated without performance of the required maintenance. Resetting the signal shall be a required step in the maintenance operation. The method for resetting the signal system shall be approved by the Administrator. For HDEs, the system must not be designed to deactivate upon the end of the useful life of the engine or thereafter.

(D) A manufacturer may desire to demonstrate through a survey that a critical maintenance item is likely to be performed without a visible signal on a maintenance item for which there is no prior in-use experience without the signal. To that end, the manufacturer may in a given model year market up to 200 randomly selected vehicles per critical emission-related maintenance item without such visible signals, and monitor the performance of the critical maintenance item by the owners to show compliance with paragraph (b)(6)(ii)(B) of this section. This option is restricted to two consecutive model years and may not be repeated until any previous survey has been completed. If the critical maintenance involves more than one engine family, the sample will be sales weighted to ensure that it is representative of all the families in question.

(E) The manufacturer provides the maintenance free of charge, and clearly informs the customer that the maintenance is free in the instructions provided under §86.087-38.

(F) Any other method which the Administrator approves as establishing a reasonable likelihood that the critical maintenance will be performed in-use.

(iii) Visible signal systems used under paragraph (b)(6)(ii)(C) of this section are considered an element of design of the emission control system. Therefore, disabling, resetting, or otherwise rendering such signals inoperative without also performing the indicated maintenance procedure is a prohibited act under section 203(a)(3) of the Clean Air Act (42 U.S.C. 7522(a)(3)).

(b)

(7)-(h) [Reserved]. For guidance see §86.094-25.

(i) Notwithstanding the provisions of paragraph (b)(4) and (6) of this section, manufacturers may schedule replacement or repair of particulate trap (or trap oxidizer) systems or catalytic converters (including NOX adsorbers), provided that the manufacturer demonstrates to the Administrator's satisfaction that the repair or replacement will be performed according to the schedule and the manufacturer pays for the repair or replacement.

[62 FR 54725, Oct. 21, 1997, as amended at 79 FR 23688, Apr. 28, 2014; 79 FR 46371, Aug. 8, 2014; 81 FR 73973, Oct. 25, 2016]