Adding Equipment To The Outside Of; Your Vehicle; Fuel; Gasoline Octane - Chevrolet 2008 Cobalt Owner's Manual

If you want to do some of your own service work,
you should use the proper service manual. It tells
you much more about how to service your vehicle
than this manual can. To order the proper service
manual, see Service Publications Ordering Information
on page 7-16.
Your vehicle has an airbag system. Before attempting
to do your own service work, see Servicing Your
Airbag-Equipped Vehicle on page 1-66.
You should keep a record with all parts receipts and
list the mileage and the date of any service work
you perform. See Maintenance Record on page 6-16.
Adding Equipment to the
Outside of Your Vehicle
Things you might add to the outside of your vehicle
can affect the airflow around it. This can cause
wind noise and can affect fuel economy and windshield
washer performance. Check with your dealer/retailer
before adding equipment to the outside of your vehicle.

Fuel

Use of the recommended fuel is an important part of
the proper maintenance of your vehicle. To help
keep the engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies your
vehicle's engine. The VIN is at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 5-104.

Gasoline Octane

If your vehicle has the 2.2L L4 engine (VIN Code F),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. If you are using gasoline rated at
87 octane or higher and you hear heavy knocking,
the engine needs service.
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