The Smog-Check-Fuel-leaks liquid fuel leak inspection shall be conducted with the engine running. Use extreme caution when working around moving parts and ensure the transmission is in “park” or “neutral” with the parking brake on.


For the purpose of conducting this inspection, a “liquid fuel leak” is defined as any fuel coming from a vehicle’s fuel delivery, metering, or evaporative systems, (1) in liquid form that has created a visible drop of fuel (or more) on a component of a vehicle’s fuel delivery, metering or evaporative system, or (2) has created a fuel puddle on, around, or under a component of a vehicle’s fuel delivery, metering, or evaporative system.



Inspection: With the engine running, the inspector shall visually inspect the following components of the vehicle, if they are exposed and visually accessible, for liquid fuel leaks:

• Gasoline fuel tanks 

• External fuel pumps 

• Carburetors   

• Charcoal canisters 

• Fuel injectors   

• Fuel delivery and return lines 

• Gasoline fill pipes – associated hoses, tanks, connections   

• Any valves connected to any other fuel evaporative component 

• Gas caps 

• Fuel vapor hoses   

• Fuel pressure regulators 

• Fuel filters



For gasoline-powered hybrid vehicles and those vehicles with stop-start systems, the inspector shall visually inspect for liquid fuel leaks with the vehicle in the key on, engine off (KOEO) position or “Ready” state (so that the vehicle’s fuel system is at its operating pressure).

Pass/Fail Criteria: If no liquid leak is found, the vehicle shall pass inspection and the inspector shall enter “P” (pass) in the EIS or OIS “Fuel Leaks” prompt. If a liquid fuel leak is detected, the vehicle shall fail inspection and inspector shall enter “F” (defective) in the EIS or OIS “Fuel Leaks” prompt. Inspectors must indicate on the vehicle inspection report (VIR) the location of any liquid fuel leak.

The liquid fuel leak procedure is a visual inspection only. Inspectors are not required to perform disassembly of the vehicle to inspect for liquid fuel leaks. No special tools or equipment, other than a flashlight and mirror, are required and no raising, hoisting, or lifting of the vehicle is required.

An inspector shall refuse to inspect or abort an inspection if a liquid fuel leak presents a safety hazard.

The liquid fuel leak shall not apply to vehicles fueled exclusively by diesel, compressed natural gas (CNG), liquefied natural gas (LNG) or liquefied petroleum gas (LPG). 




When entering the correct definition for a fuel leak under visual inspection you must enter the information correctly for that particular vehicle and model year. The EIS or the OIS both have different inputs, and you must know this on the State exam.

Here is a list of some of the inputs for tampering, remember from 1976 - 1999 will have a different input than a 2000 and newer vehicle.

F = Defective

D = Disconnected 

M = Modified 

T = Tampering  

S = Missing 

If a vehicle has tampered "A.I.R" air injection reactor system on a 1997 Chevrolet, you discover  the hoses are connected incorrectly that you found during a visual inspection how would you input this information.?

If there is a gasoline leak discovered prior to the inspection that's a safety hazard abort the test

Remember on Diesels the visual fuel leak test is not performed. 

Answer: M- Modified

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