Missouri Code of State Regulations
Title 11 - DEPARTMENT OF PUBLIC SAFETY
Division 50 - Missouri State Highway Patrol
Chapter 2 - Motor Vehicle Inspection
Section 11 CSR 50-2.280 - Air Pollution Control Devices

Universal Citation: 11 MO Code of State Regs 50-2.280

Current through Register Vol. 49, No. 18, September 16, 2024

PURPOSE: This rule describes the procedures and standards for the inspection of air pollution control devices. The inspection of air pollution control devices is a requirement of section 307.365, RSMo.

(1) The inspection of air pollution control devices installed by the manufacturer will apply to 1968 and later model vehicles. This does not apply to diesel fuel vehicles or to vehicles operating exclusively on propane fuel or compressed gas. Vehicles converted with option to operate on compressed natural gas or propane are permitted to remove or modify the thermostatic air cleaner if the modifications performed meet United States Environmental Protection Agency Mobile Source Enforcement Memorandum Number 1A.

(A) Effective July 1, 1992, all light-duty vehicles which are passenger vehicles with a Gross Vehicle Weight Rating (GVWR) below six thousand pounds (6,000 lbs.) and commercial vehicles with a GVWR below eight thousand five hundred pounds (8,500 lbs.), which receive a replacement engine, in regard to all emissions related parts, engine design parameters and engine calibrations, must comply with the certified configuration of the same or newer model year as the vehicle chassis.

(B) Effective July 1, 1992, diesel powered vehicles may receive a replacement gasoline engine if the resulting engine-chassis configuration is equivalent to a certified configuration of the same model year or newer as the chassis and that chassis has been certified with a gasoline engine.

(C) Effective July 1, 1992, heavy-duty vehicles which are passenger vehicles with a GVWR in excess of six thousand pounds (6,000 lbs.) and commercial vehicles with a GVWR in excess of eight thousand five hundred pounds (8,500 lbs.) may receive a replacement heavy-duty engine if the resulting vehicle is identical to a certified configuration of the same model year or newer. Under no circumstances may a heavy-duty engine ever be installed in a light-duty vehicle.

(D) All 1968 and later model vehicles which received a replacement engine before July 1, 1992, must be equipped with all the air pollution control devices installed by the manufacturer on that particular engine.

(E) Reject vehicle if a:
1. Replacement engine is not equivalent to the certified configuration of the engine-chassis; or

2. Heavy-duty engine is used in a light-duty chassis.

(2) Crankcase Ventilation.

(A) The ventilation system of the crankcase is commonly known as the positive crankcase ventilation (PCV) system. The engine should be warm and running at idle during inspection of the vent system.

(B) Inspect plumbing connections for tightness and proper routing. Disconnect PCV valve from engine. Shake briskly and listen for a rattling sound. Place finger or thumb over end of valve and feel for vacuum suction.

(C) Reject vehicle if:
1. Plumbing is loose, broken, leaking or improperly routed;

2. No vacuum suction is present or valve does not rattle when shaken; or

3. Any part of the system is missing or disconnected.

(3) Air Injection System.

(A) The air injection system provides air to the exhaust manifold or catalytic converter. The system may or may not be equipped with an external air pump.

(B) With engine stopped, inspect tension of air pump drive belt. Inspect hose connections at air pump, antibackfire valve, check valves and air distribution manifolds.

(C) Reject vehicle if:
1. Belt slips or is frayed, if serpentine air pump belt has sections missing, if connections are loose, broken or leaking; or

2. Any part of the injection system is missing or disconnected.

(4) Engine Modification Type.

(A) An engine modification control system may be most easily identified as one without an air pump.

(B) With engine stopped, inspect ignition wiring and vacuum hose connections.

(C) Reject vehicle if:
1. Wires or connections are loose, broken or leaking; or

2. Any part of system is missing.

(5) Thermostatic Air Cleaner.

(A) The thermostatic air cleaner provides heated air to the carburetor during cold-engine operation.

(B) Inspect exhaust manifold shroud, preheat tube, vacuum diaphragm air cleaner and vacuum hoses.

(C) Reject vehicle if:
1. Connections are broken or disconnected; or

2. Any part of system is missing.

(6) Spark Control System.

(A) The spark control system controls the advance and retard of the ignition spark.

(B) Inspect distributor, vacuum control valve, electrical control switch, wiring and vacuum hoses.

(C) Reject vehicle if:
1. Wiring or vacuum lines are broken, leaking or improperly routed; or

2. Any part of the system is missing or bypassed.

(7) Exhaust Gas Recirculation.

(A) The exhaust gas recirculation system supplies metered exhaust gas to the intake manifold.

(B) Inspect exhaust gas recirculation valve, temperature control valve and vacuum lines for proper routing.

(C) Reject vehicle if:
1. Components are broken, leaking or improperly routed; or

2. Any part of system is missing.

(8) Oxygen Sensor System.

(A) The oxygen sensor system measures the quantity of oxygen present in the exhaust system and supplies a signal to the carburetor or fuel injection system.

(B) Inspect oxygen sensor, located in exhaust manifold, temperature sensor, crankshaft sensor, microprocessor and wiring for proper routing.

(C) Reject vehicle if any:
1. Component is leaking, bypassed, modified or disconnected; or

2. Part of the system is missing.

(9) Evaporative Emission System.

(A) The evaporative emission system restricts the release of fuel vapors by storing and metering the fuel vapors into the fuel intake system.

(B) Inspect the fuel tank vent line, overfill limiting valve, charcoal canister and purge line for proper mounting, leaks and proper routing.

(C) Reject vehicle if:
1. Components are leaking, improperly routed or mounted; or

2. Any part of the system is missing or disconnected.

(10) Catalytic Converters.

(A) All 1981 and later model vehicles which were equipped by the manufacturer with a catalytic converter(s) must be equipped with the original equipment manufacturer converter(s) or United States Federal Environmental Protection Agency-approved replacement converters. These devices are located in the exhaust system, usually in front of the muffler.

(B) Inspect catalytic converter.

(C) Reject vehicle if:
1. Catalytic converter is bypassed or modified, is not securely attached, has leakage or is patched by other than an arc or acetylene weld; or

2. A 1981 or later model vehicle is not equipped with a catalytic converter, as equipped by the manufacturer and as specified on the emission label.

*Original authority: 307.360, RSMo 1967, amended 1971, 1973, 1979.

Disclaimer: These regulations may not be the most recent version. Missouri may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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