Oldsmobile 2003 Silhouette Owner's Manual page 207

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
See Gasoline Octane on page 5-5. Poor fuel quality
will cause your engine not to run as efficiently as
designed. You may notice this as stalling after start-up,
stalling when you put the vehicle into gear, misfiring,
hesitation on acceleration or stumbling on acceleration.
(These conditions may go away once the engine is
warmed up.) This will be detected by the system and
cause the light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic tools to fix any mechanical or electrical
problems that may have developed.
Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON or CHECK ENGINE light is on or not
working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, see your dealer or qualified service
center to prepare the vehicle for inspection.
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