This module covers general information about the
Smog Check Program and inspection procedures. It is not all inclusive and
does not replace or supersede any applicable Smog Check or Automotive
Repair Act laws and regulations. In this module, we will present the following
elements of the Smog Check inspection process: Visual inspection
Emissions test Functional tests
Inspection results The Smog Check inspection
includes the following elements: A visual inspection is performed to ensure that
the vehicle's emission components are present, properly connected, and have not been modified.
An emissions test is then conducted to determine the actual composition of the exhaust gases.
The emissions test is followed by several functional tests that are performed to confirm
the operation of certain emission components. Inspection results are transmitted to
the Vehicle Information Database, or VID. During the visual inspection, the Inspector
identifies the vehicle being tested and checks that the required emission control
systems are on the vehicle and properly operating. Some vehicles may have aftermarket
performance parts that need to be inspected for Air Resources Board certification
and correct Executive Order number. The Inspector is also required to check for
liquid fuel leaks for applicable vehicles. The visible smoke test for gasoline engines
consists of a visual inspection of a vehicle's engine crankcase and tailpipe for signs of
smoke while the engine is at idle and during a BAR-specified snap test. The BAR snap test
will be discussed later in this presentation. The Smog Check Inspector verifies that the
vehicle matches the registration renewal form and scans the information into the
Emissions Inspection System, or EIS. The EIS accesses the VID to determine if the
station is authorized to inspect the vehicle. After verifying that the vehicle information
matches the Department of Motor Vehicles renewal, the renewal form may be used to
enter information into the EIS, only after verifying that it
matches the vehicle being tested. If necessary, the Inspector can enter the
vehicle identification information manually. Inspectors must use all available information
necessary to determine the vehicle's emission control requirements,
including but not limited to: Correct underhood emission control label
Current emission control application guide Emission control repair manuals
Emission component location guides Manufacturer emission control recalls
and Technical Service Bulletins, or TSBs Vacuum hose routing diagrams
California Air Resources Board, or ARB, aftermarket parts listings and,
Aftermarket parts label Using the proper reference material and
the vehicle's underhood emission control information label, the Inspector examines
the vehicle to see if the required systems are installed and properly connected.
The EIS provides screen prompts that direct the Inspector to visually inspect
the vehicle's emission control systems. For each system, the Inspector manually enters
one of the following into the EIS prompt: P for Pass
S for Missing M for Modified
D for Disconnected F for Defective
N for Not Applicable The Inspector checks whether each
required emission control system or component is missing, modified, or disconnected. A Missing emission control system or component is one in which all or part has been
removed from the vehicle or engine. An emission control system or component is
Modified if it has been disabled, replaced with a component not approved for installation on that
vehicle, replaced with a component not approved for street use, or replaced with a component
that does not function properly as designed. An emission control system has been
Disconnected if any hose, wire, belt, or other component required for the operation of
the emission control system has been disconnected. The term Defective applies to an emission control
system or component that is worn, deteriorated, or broken, which will affect the operation
of an emission control component or system. It is not a condition that
occurred as a result of tampering. Examples of defective devices can be a
hose, wire, cap, or thermal valve or switch, disturbed and not reconnected or
corrected when the vehicle was serviced. Inspectors should refer to the correct underhood
label and/or applicable reference materials to identify all required emission control systems
for the vehicle. The following slides will discuss these systems in more detail. Please
be aware this is not an all-inclusive list. The Positive Crankcase Ventilation
system routes blow-by gases from the crankcase to the intake manifold to
reduce hydrocarbons and carbon monoxide. The Thermostatic Air Cleaner system supplies
warm air during cold engine operation by allowing heated air from the
exhaust into the air intake. During the visual inspection, the Inspector
must check that the required exhaust shroud, hot air duct, thermostatic vacuum switches, vacuum hoses, and air cleaner components
are present and installed properly. An air cleaner lid installed upside
down would be considered modified. There are several types of Air Injection Systems, such as electric and belt driven
air pumps and pulse air systems. All introduce fresh air into the exhaust system to
reduce hydrocarbons and carbon monoxide emissions. During the visual inspection, the Inspector must check that the Air Injection System
is present and properly connected. The Fuel Evaporative System prevents fuel vapors from escaping and contributing
to smog-forming hydrocarbons. During the visual portion of the Fuel
Evaporative System inspection, the Inspector must check for the presence of a vapor storage
canister and ensure that the required hoses, solenoids, etc., are connected properly. It
is also necessary to check for the proper fuel tank cap and any non-OEM or auxiliary fuel
tanks and associated fuel vapor canisters. Inspectors are not required
to perform disassembly of the vehicle to inspect the fuel evaporative system. The Exhaust Gas Recirculation system is designed
to reduce oxides of nitrogen by directing exhaust gases into the intake manifold during certain
modes of engine operation. EGR valves can come in a variety of designs and are typically controlled
by engine vacuum and/or electronic controls. If an EGR system is required for the vehicle, the Inspector must verify that it
is present and properly connected. The Inspector should refer to
the vehicle's underhood label and/or use Emission Control System Application
Guides to determine the proper EGR requirements. and is designed to maintain
an optimal air/fuel ratio. When the optimal air/fuel ratio
is maintained, the catalytic converter can control oxides of nitrogen,
hydrocarbon, and carbon monoxide emissions. The Computerized Engine Control system consists
of a Powertrain Control Module, or PCM, input devices such as sensors and switches,
and various actuators controlled by the PCM. The Inspector should be sure to check for
the presence of required sensors such as, but not limited to, the Oxygen
Sensor, Manifold Air Pressure Sensor, Coolant Temperature Sensor,
and Throttle Position Sensor. The Inspector should also check for any
tampering of computerized engine controls. Fuel injectors and carburetors
control fuel delivery to the engine. The fuel metering system is examined to confirm
that the proper components are installed. A fuel metering system may include: air-flow
meters, injectors, fuel pressure regulators, throttle bodies, throttle positioners,
anti-dieseling solenoids, early fuel evaporation devices, carburetor, choke
controls, deceleration controls, and dashpots. The Oxygen Sensor or Air Fuel Ratio Sensor
is located in the exhaust manifold or pipe. There may also be sensors after the catalyst. Oxygen sensors compare the level of
ambient oxygen to the level of oxygen in the exhaust stream and send a variable signal
to the vehicle's Powertrain Control Module. Refer to the proper reference materials
and underhood label to confirm the number and location of the sensors. Ensure that
the Oxygen Sensors are properly installed. Ignition Spark Controls are
mechanical or electronic devices that control ignition timing.
The Inspector must check to ensure that all parts of the spark control system
are present and connected properly. The catalytic converter is
designed to convert hydrocarbons, carbon monoxide, oxygen, and oxides of
nitrogen into carbon dioxide and water. Most vehicles built from 1975 to present, are
equipped with one or more catalytic converters. Some vehicles have the catalytic
converter located in the exhaust manifold, but most are located between the
exhaust manifold and the muffler. Vehicles with multiple CATs have some
located near the exhaust manifolds commonly known as pre-catalytic
converter or warm up catalytic converter. A multitude of cars, in each one, a motor burns
fuel and produces toxic gases; nitrogen oxides, carbon monoxide, and unburnt fuel residue.
Luckily each car also has a catalytic converter located under the hood, attached to the
motor, right before the exhaust system. Gases produced by the motor go
straight into the catalytic converter and come out the other side less
than a tenth of a second later. The converter gets less than a tenth of a second
to recombine toxic gas molecules and produce harmless substances like water vapor and oxygen.
How? To understand it, we’ve got to destroy it. The stainless-steel housing contains
two ceramic blocks. Each block is filled with thousands of micro-ducts. Their
sides are coated with precious metals. Precious? Platinum and rhodium in the first
block. Platinum and palladium in the second block. Metals that can cost more than $100,000
a pound, but they are worth every penny. Together they have the extraordinary
property of causing toxic gases to react and then recombine, producing
gases that are harmless to your health. All that without altering themselves or rusting.
Precious. The trick is to maximize the contact zone between gas and metals. That’s why there’s
so many micro-ducts, almost 400 per square inch. Their combined surface area
matches that of a football field. A laboratory as big as a football field but
folded onto itself in order to remain small. The transformation of gas from toxic
to nontoxic happens most efficiently when the catalytic converter is hot.
Very hot. 1,300 degrees Fahrenheit. It’s the toxic gases themselves that heat up
the catalytic converter. They exit the motor at temperatures as high as 900 degrees Fahrenheit.
The chemical reactions inside the catalytic converter also generate heat, transforming the
converter into a super-efficient furnace designed to break down and reform gas molecules. Let’s take
a closer look at these mysterious transformations. The nitrogen oxide and carbon monoxide molecules
along with the molecules of unburnt fuel residue enter the catalytic converter. They’re
swallowed up by the thousands of micro-ducts. As they reach the platinum and rhodium in the
first block, nitrogen oxide molecules are the first to react. These metals breakdown the
molecules by withholding one of their atoms. The freed atoms stick to each other and
recombine. The result? Nitrogen oxide molecules become oxygen and nitrogen which already makes up
ninety-nine percent of the air that we breathe. The gas molecules now head into the second block
where the micro-ducts are coated in platinum and palladium. Theses precious metal withhold oxygen.
The intense heat here forces the carbon monoxide molecules to combine with the oxygen. The result?
Carbon monoxide. The same gas that creates bubbles in soft drinks. Now for the molecules of unburnt
fuel residue. At these extreme temperatures, their encounter with the oxygen forces them to
recombine. The result? More carbon dioxide and water. All that in less than a tenth of a second.
In theory, the catalytic converter can eliminate ninety-nine percent of a motor’s toxic gases. In
reality, it’s inefficient as long as it’s not hot. A car has to travel about six miles before
the catalytic converter reaches its ideal operating temperature. That’s six miles
spewing untreated gases. In spite of the catalytic converter’s best efforts, the car
remains a source of pollution. But, thanks to this miniature laboratory it emits five times
less pollution. That’s still pretty impressive. The Inspector must verify the correct
number, application, location, and orientation of the catalytic converter,
as specified by the vehicle manufacturer. If a vehicle is equipped with parts that modify
the original emission control configuration, Inspectors must verify whether those
parts are ARB approved or exempted. If the installed parts are
not ARB approved or exempted, and the original emissions control configuration
has been modified, the corresponding emission controls are considered Modified and
the vehicle shall fail the inspection. Aftermarket parts guidelines
for gasoline and diesel vehicles are found in Appendix C of the Smog Check Manual. A missing or illegible aftermarket parts label
does not constitute an inspection failure. In cases where the label is missing or illegible,
the Inspector may proceed with the inspection, provided the parts can be confirmed as ARB
approved or exempted by comparing the part number marked on the part with the ARB Executive Order
parts listings or the parts manufacturer catalog. This is a screenshot directly from the ARB
website showing the search engine for EO numbers, or search by EO or manufacturer
for the device type. This screenshot confirms that the EO part number
for the cold air intake system matches the vehicle application. This would be a Pass in the Other
Emissions Related components category of the EIS. A liquid fuel leak means any fuel emanating from
a vehicle's fuel storage, delivery, metering, or evaporation system in liquid form that
has created a visible drop or more of fuel. The fuel leak can be visible on a
component of a vehicle's fuel delivery, metering, or evaporation system,
or has created a puddle on, around, or under a component of a vehicle's
fuel delivery, metering, or evaporation system. The 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. The liquid fuel leak shall not apply to
vehicles fueled exclusively by diesel, compressed natural gas, liquefied
natural gas, or liquefied petroleum gas. Nothing in the liquid fuel leak inspection shall
prohibit an Inspector from refusing to inspect a vehicle or from aborting an inspection if a
liquid fuel leak presents a safety hazard. The liquid fuel leak procedure
is a visual inspection only. If no liquid leak is found, the
vehicle shall pass inspection and the Inspector shall enter “P” for Pass in the
Emissions Inspection System Fuel Leaks prompt. If a liquid fuel leak is detected, the vehicle
shall fail the inspection and the Inspector shall enter “F” for Defective in the Emissions
Inspection System Fuel Leaks prompt. The Inspector must indicate on the Vehicle Inspection
Report, the location of any liquid fuel leak. 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. The visible smoke test has three parts: During the idle test, the Inspector
observes the tailpipe exhaust plume for 10 seconds after performing
the emissions test on the vehicle. For the crankcase test, the Inspector
observes the engine crankcase for 10 seconds. The Inspector performs the BAR
snap test by quickly pushing and releasing the accelerator
pedal from the idle position. Visible smoke test results
are entered into the Other Emission Related controls category of the EIS. When using the BAR OBD
Inspection System, or BAR-OIS, you will be prompted when to conduct the visible
smoke test and where to enter the results. The following video provides detailed
procedures for this test using the EIS. There are several steps that must be followed
before conducting the visible smoke test. First, place the transmission in
Neutral or Park, with the parking brake on and/or wheel chocks in place. Turn off
all accessories, including the air conditioning. Next, ensure the vehicle is at
normal operating temperature, as described in the Smog Check Manual. Finally, position the vehicle to ensure there
are no drafts that can disturb the exhaust plume. Make sure there is nothing in the shop
environment, such as equipment or toolboxes, which would prevent you from
clearly observing the exhaust plume. The first part of the check for visible smoke
is a BAR snap test. This test consists of pushing the accelerator pedal quickly from the
idle position to between 2,000 and 3,000 RPM, then immediately releasing it
to allow the engine to return to idle for at least three seconds
between each snap of the accelerator. There are three BAR snaps that must be performed.
The first BAR snap is performed before conducting the ASM or Two-Speed Idle tests. This snap will
help you to become familiar with the vehicle. Do not check for tailpipe smoke
during this first BAR snap test. The engine RPM may be viewed using the vehicle's
tachometer or the analyzer screen immediately prior to the emissions test. You may also use an
auxiliary tachometer to conduct the BAR snap test. The final two BAR snap tests are conducted later when the analyzer prompts for the
Other Emissions Related components. For gasoline powered vehicles, the idle test
shall be performed immediately after performing the Smog Check emissions test. Upon completing
the emissions test, leave the engine running. Remove the exhaust probe from the tailpipe.
With an unobstructed view, watch the vehicle's tailpipe exhaust plume for 10 seconds. If smoke
is observed, the vehicle shall Fail inspection. Be aware that water vapor or steam
is not considered visible smoke and would not cause a vehicle
to fail the visible smoke test. The crankcase test should be performed during
the visual check of a vehicle's emissions control systems. With the engine idling, observe
the engine crankcase system for 10 seconds. If smoke is observed the
vehicle shall Fail inspection. Smoke observed from any area
other than the crankcase system regardless of the cause, does not constitute
a crankcase visible smoke test failure. The final two BAR snaps are to be performed at the
time the analyzer prompts for the Other Emission Related components. Perform the second BAR snap
while watching for visible smoke from the vicinity of the tailpipe. Return the engine to idle and
wait for at least 3 seconds to allow the engine to stabilize. Now perform the third-and-final
BAR snap while watching for visible smoke. If any smoke is observed while conducting these final
two snaps, the vehicle shall Fail inspection. In this example, smoke was observed,
and the vehicle would fail inspection. Please note that visible smoke can most often
be seen between 0 and 10 feet from the tailpipe. This completes the visible smoke test
inspection procedures. Now, let's take a look at the Pass/Fail determination criteria.
If no smoke is observed during the idle test, the crankcase test, or the BAR snap test, the vehicle
shall Pass the visible smoke test. If any smoke is observed during any one of the three tests, the
idle test, the crankcase test or the BAR snap test, the vehicle shall Fail the visible smoke
test. Here is an example of a vehicle emitting tailpipe smoke during the tailpipe idle test.
This vehicle would Fail the visible smoke test. After completing the visible smoke test,
enter the test results into the analyzer. The results must be entered into the
Other Emission Related controls category of the visual portion of
the Smog Check inspection. However, the analyzer currently allows only one
entry for the visual inspection of all components covered under the Other Emission Related controls
category. Therefore, if the vehicle passes all three parts of the visible smoke test but fails a
visual check of any other component covered under the Other Emission Related controls category,
enter the appropriate failure code. “P” for Pass, ”D” for Disconnected, “M” for Modified,
“S” for Missing, or “F” for Defective. Similarly, if a vehicle passes a visual check of
any components covered under the Other Emission Related controls category, but fails any one of
the visible smoke tests, enter “F” for Defective. If the vehicle fails the visible smoke test,
the technician is required to document the failure on both the customer's copy and the
station's copy of the Vehicle Inspection Report, VIR. The failure also must be
noted on the customer's invoice. Make a clear notation such as “Failed Visible
Smoke Test” or “Failed for Visible Smoke.” In addition, specify what part(s) of the
visible smoke test the vehicle failed. For example, technicians may use terms like
“Crankcase Test Smoke,” “Idle Test Smoke,” or “BAR Snap Test Smoke”. If applicable, list multiple
reasons for the visible smoke test failure. This section briefly describes
the Emissions Inspection System, and procedures for performing a
tailpipe emissions test of the vehicle. The Inspector places the probe in the tailpipe
to perform either an Acceleration Simulation Mode or Two-Speed Idle test. The type of test required
depends upon the vehicle and program area. The Emissions Inspection System consists of
a 5-gas emission analyzer, a fuel cap tester, and in most cases, a dynamometer. The Emissions Inspection System is used to
perform the Acceleration Simulation Mode test and the Two-Speed Idle test. The Acceleration Simulation Mode emission
test is performed by placing the vehicle being tested on a dynamometer; a treadmill-like
device that simulates actual driving conditions for a more accurate measurement of
the pollutants a vehicle produces. The vehicle is driven on the
dynamometer at 15 miles per hour, and again at 25 miles per hour. The
calculated load is determined by the EIS. The EIS can perform the Two-Speed Idle
emissions test when an ASM test is not required, or on vehicles that cannot be
physically tested on the dynamometer. For example, a vehicle with a full-time four-wheel
drive, or a non-disengagable traction control, cannot be tested on a dynamometer.
The Two-Speed Idle test includes two test sequences: a 30 second 2,500
RPM test and a 30 second idle test. A functional test must be performed
on vehicles, when applicable. This slide indicates the functional
tests needed for each vehicle, depending upon model-year, weight,
fuel type, and equipment applications. All 1995 model-year and older
vehicles equipped with an EGR system and subject to a Two-Speed Idle test
shall undergo the EGR system functional test. Vehicles that undergo an ASM Test would
not need an EGR system functional test, because the EGR system operation is reflected in
the sample reading collected from the ASM test. Inspectors must follow the functional test
procedures prescribed by the vehicle manufacturer. All 1995 model-year and older vehicles equipped
with EGR, and subject to a Two-Speed Idle, TSI, are required to have an
EGR functional test performed. The EGR’s main function is to help reduce NOx
emissions. Since the TSI test does not measure for NOx emissions, as with the ASM test, the EGR
system needs to be tested for proper operation.
The technician must follow the
functional test procedures in the vehicle manufacturer service manual or
the Emissions System Application Guide, as there are several different types of
EGR systems depending upon application.
Some EGRs are electronically operated,
as in the example shown here. Other ERG systems are vacuum operated.
In this example of an EGR functional test, this
system is vacuum operated. The system first needs testing for a proper vacuum supply reaching
the EGR valve under appropriate conditions.
Then the EGR valve and EGR passages
need to be tested for proper flow. With the engine running, apply a vacuum to the EGR
valve. If the valve opens and the passages have proper flow, the engine should stumble or stall.
Now let's look into the basics of ignition timing. It is the process of setting the point at which
the spark will occur in the combustion chamber, relative to piston position and crankshaft angle.
Ignition timing is measured in degrees Before Top Dead Center and is usually adjusted
by rotating the engine's distributor. On late-model vehicles, the
Powertrain Control Module adjusts ignition timing based on engine control sensors. Inspectors must check the base ignition timing
using vehicle manufacturer procedures. Many underhood emission labels provide procedures and
specifications for checking the ignition timing. If no label is present or if the procedures are
not on the label, the Inspector must refer to an Emission Control Systems Application Guide
or appropriate service manuals. If no RPM is specified for the timing check, the idle speed
must be within 100 RPM of the base idle speed. To pass inspection, the base ignition timing
must be at manufacturer specification, plus or minus three degrees. If the timing is found to be more than
three degrees in either direction from manufacturer specification, the
vehicle fails the functional test. If the manufacturer provides
a timing specification range, the three-degree tolerance is not allowed. Engine speed must be within
the specified RPM range. If the underhood emissions control label, and emissions application guide, or other
reliable manufacture derived references indicates timing is not adjustable, then
the ignition timing test is not required. If the timing cannot be measured
due to a mechanical defect, such as a slipped harmonic balancer,
the vehicle shall fail the timing test. The EIS includes a provision to
account for mechanical defects. Follow the EIS prompts and document the mechanical
defect on the Vehicle Inspection Report. The vehicle's base ignition timing shall be
checked using the manufacturer procedures.
Many underhood emissions labels provide procedures
and specifications for checking ignition timing.
In this example, the ignition timing is computer
controlled and as the underhood label indicates, the base timing is 10 degrees
BTDC, Before Top Dead Center, with the diagnostic connector short-circuited
in order to check the base timing at idle.
The timing needs to be within plus-or-minus
3 degrees of manufacturer specifications or within the range provided by
the manufacturer if specified.
The timing needs to be checked at
idle speeds plus-or-minus 100 RPM of manufacturer specified idle, unless otherwise
specified by the timing procedure provided.
Procedures can also be found in the
Emissions Control Application Guide or an appropriate service manual.
Vehicles listed to have “not adjustable” timing and/or vehicles with
computer-controlled ignition systems that do not have “timing adjustments,” are
exempt from the ignition timing test, even if the timing specifications are listed.
Any mechanical defects, where the timing cannot be measured, will be entered as a Fail for the
ignition timing portion of the smog inspection. All 1996 model-year and newer vehicles have
computer-controlled emission control systems, which have on-board diagnostic capabilities. Vehicles are equipped with standardized
diagnostic data link connectors, or DLC, which the inspection systems, both EIS and OIS,
can connect to and collect diagnostic information. The Smog Check OBD II functional test evaluates
and reports the status or results of the readiness monitors. This is automatically performed
by the inspection systems, both EIS and OIS. The location of the DLC can be
found in appropriate electronic component location manuals or emission
control diagnostic and repair manuals. The DLC may provide a RPM signal, that in most
cases, can be used during emission test sequences. The inspection systems, both EIS and OIS, assess
the OBD II’s systems ability to communicate the readiness of system monitors, the diagnostic
trouble codes, and MIL command status. DLCs are typically located on the driver's
side, underneath the instrument panel, but some can be located in the center console
or on the passenger side of the vehicle. A cable from the inspection system, either
EIS or OIS, is connected to the vehicle's DLC to check for trouble codes and monitor status
stored in the Powertrain Control Module. The Malfunction Indicator Light, or Check Engine
Light, shall be checked on all vehicles equipped with an OBD I or OBD II system. To check MIL
function, the Inspector must turn the ignition to the Key-On-Engine-Off position, observe the MIL,
and then start the engine, Key-On-Engine-Running. The MIL should be on in the Key-On-Engine-Off
position and turn off when the engine is started. A Pass entry indicates the MIL properly operates and service or repairs are not needed.
A Fail entry indicates the MIL is not on with Key-On-Engine-Off, stays on,
or flashes with the engine running. When applicable, the Malfunction Indicator
Light, MIL, or the Check Engine Light, shall be checked on all vehicles equipped with an On-Board
Diagnostics system I or II, or OBD I or OBD II.
To check the MIL function, the technician shall
turn the ignition key to the Key-On-Engine-Off, KOEO, position and observe the MIL
operation. The MIL should illuminate.
The technician should then start the
engine, Key-On-Engine-Running, KOER. The MIL should extinguish when the engine is
started or within a few seconds of starting.
A MIL that does not illuminate in the KOEO
position or stays on continuously after engine is started, is entered as a Fail for the
MIL functional test of the smog inspection.
The Smog Check OBD II functional test evaluates
and reports the status and/or results of the readiness indicators, system faults, and MIL.
The process is an integral part of the Smog Check Inspection, requiring minimal technician input.
The technician must always use all available information necessary to determine the
vehicle's OBD II requirements, including but not limited to, the underhood emissions
control label, an underhood vacuum diagram. Many publications are also available such as
a current Emissions Control Application Guide, emission control repair manuals, emission
component locations guides, manufacturer emission control recalls, BAR OBD technical advisements,
and any reliable vehicle manufacturer sources. This test applies only to 1995 model-year
and older vehicles equipped with evaporative emission control systems. During the fuel cap
integrity functional test, the Inspector must: Refer to the fuel cap tester application
manual to determine if there is a cap adapter available for the vehicle being tested.
If none, enter No adapter is available. Follow the EIS and fuel cap tester
prompts to complete the test. The test results are manually entered
by the Inspector into the EIS. As prompted by the EIS, perform the fuel cap
integrity test on all 1976 to 1995 vehicles equipped with evaporative controls that operate
on a gasoline, including dual/bi-fueled vehicles. The fuel cap integrity test is a two-part test
made up of a visual and a functional test.
For the visual inspection, inspect the fuel cap or
caps for proper fit and installation. If the fuel cap threads are stripped, or the fuel cap seal is
missing or damaged, the cap would fail inspection. If the fuel cap is not designed for the vehicle,
the fuel cap shall fail the visual inspection.
The inspection result entries are “P” for
Pass, “F” for Fail, and “S” for Missing.
The functional check applies only to vehicles with
evaporative emission control systems. Check the fuel cap tester application manual, if needed,
to select and input the correct cap adaptor. Following the EIS and cap tester
prompts, attach the fuel cap or caps, one at a time, to the
adapter and perform the test.
Assure the fuel cap is
securely attached and sealed.
The fuel cap is automatically tested
for its ability to hold a proper seal.
When prompted, remove the
fuel cap from the adapter.
The test results are automatically
captured by the EIS as a Pass or Fail.
If the fuel cap fails, the EIS will
give you an option to replace the fuel cap and retest the new cap for a proper seal. When the EIS has finished testing the first
fuel cap, the technician is then given a choice to test a second cap if applicable.
If no adapter is available from the tester manufacturer, for the vehicle being
tested, or the vehicle is newer than 1995, do not perform the functional test, enter “No
adapter is available,” as prompted by the EIS. The main components of the fuel evaporative system
are: evaporative canister, sealed fuel tank, liquid-vapor separator, and vent
lines to a vapor storing canister filled with activated charcoal or carbon. The filler cap is not vented to the atmosphere and is fitted with a valve to allow
both pressure and vacuum relief. All OBD II controlled vehicles monitor
the EVAP during vehicle operation to determine system integrity. The Low-Pressure Fuel Evaporative Test is
required on 1995 and older model-year vehicles and checks the vehicle's fuel tank
and evaporative system for leaks. During the test, the vapor hose is pinched
off at the canister to seal the system. The LPFET tester is then used to pressurize
the fuel tank to approximately 0.5 psi. When the system reaches the proper pressure, the tester
monitors the system for excessive pressure drop. The tester makes a pass/fail
decision based on how much pressure the system was able to retain
over a specified amount of time. This is an example of a typical fuel evaporation
control system. The vapor hose is pinched off as close to the canister as feasible to
seal as much of the system as possible. BAR has certified two
manufacturers to produce LPFET equipment. Both systems include
the following components: A tester
A device to manually calibrate the tester Filler neck adaptors to attach the tester to
the vehicle in place of the fuel filler cap Pliers to pinch off the vapor
hose and seal the system A calibration tank
The EIS transmits vehicle test results to the state's central database also
known as the Vehicle Information Database, or VID. Following the test, the EIS prints out two copies
of the test results. The Inspector signs and dates the VIR under penalty of perjury. A copy is
retained by the Smog Check station and the second copy must be provided to the consumer.
All test results are stored on the VID. If the vehicle passes the test, a Certificate
of Compliance is electronically transmitted to the Department of Motor Vehicles
to meet registration requirements. Thank you for viewing Module 2 of the
California Smog Check Program training series.