Saturn 2004 Ion - Manual (Page 250)

When to Change Engine Oil
(GM Oil Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated
can vary considerably. For the oil life system to
work properly, you must reset the system every time
the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHG OIL message will come on.
See Change Engine Oil Message on page 3-43 for
more information on this message. Change your oil as
soon as possible within the next two times you stop
for fuel. It is possible that, if you are driving under the
best conditions, the oil life system may not indicate
that an oil change is necessary for over a year.
However, your engine oil and filter must be changed at
least once a year and at this time the system must
be reset. Your retailer has trained service people who
will perform this work using genuine Saturn parts
and reset the system. It is also important to check your
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Oil Life System
The GM Oil Life System calculates when to change
your engine oil and filter based on vehicle use.
Anytime your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to the
CHG OIL message being turned on, reset the system.
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