7-6
Starting and operating
in order to meet their obligation under
federal law to implement stricter vehicle
emission standards to reduce air pollution
from vehicles. A dynamometer is a tread-
mill or roller-like testing device that allows
your vehicle’s wheels to turn while the
vehicle remains in one place. Depending
on the severity of a state ’s air pollution
problems, the states must adopt either a
“basic ”or “enhanced ”vehicle emission
inspection test. Normally, a portion of the
basic emission test consists of an emis-
sion inspector inserting an analyzer probe
into the exhaust pipe of an idling vehicle
for a short period of time. States with more
severe air pollution problems are required
to adopt an enhanced vehicle emission
test. This test simulates actual driving
conditions on a dynamometer and permits
more accurate measurement of tailpipe
emitted pollution than the basic emission
test.
The U.S. Environmental Protection
Agency (EPA) and states using two-wheel
dynamometers in their emission testing
programs have EXEMPTEDSUBARU
AWD vehicles from the portion of the
testing program that involves a two-wheel
dynamometer.
There are some states that use four-wheel
dynamometers in their testing programs.
When properly used, that equipment will not damage an AWD SUBARU vehicle.
Under no circumstances should the rear
wheels be jacked off the ground, nor
should the driveshaft be disconnected for
state emission testing.
The EPA has issued regulations for
inspecting the On-Board Diagnostic
(OBD) system as part of the state emis-
sions inspection. The OBD system is
designed to detect engine and transmis-
sion problems that might cause vehicle
emissions to exceed allowable limits.
These inspections apply to all 1996 model
year and newer passenger cars and light
trucks. Over 30 states plus the District of
Columbia have implemented the OBD
system inspection.
.
The inspection of the OBD system
consists of a visual operational check of
the “CHECK ENGINE ”warning light/
malfunction indicator lamp (MIL) and an
examination of the OBD system with an
electronic scan tool while the engine is
running.
. Avehicle
passes the OBD system
inspection if proper the “CHECK EN-
GINE ”warning light/MIL illumination is
observed, there is nostored diagnostic
trouble codes, and the OBD system
readiness monitors are complete.
. A vehiclefails the OBD inspection if the “
CHECK ENGINE ”warning light/MIL is
not properly operating or there is one or
more diagnostic trouble codes stored in
vehicle ’s computer with the “CHECK
ENGINE ”warning light/MIL illuminated.
. A state emission inspection may reject
(not pass or fail) a vehicle if the number of
OBD system readiness monitors “Not
Ready” is greater than one. Under this
condition, the vehicle operator should be
instructed to drive his/her vehicle for a few
days to set the monitors and return for an
emission re-inspection.
. Owners of rejected or failing vehicles
should contact their SUBARU Dealer for
service.
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