Chevrolet Cobalt Service & Repair Manual: Automatic Temperature Control Diagnosis & Testing

Air Conditioning & Heater

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ATC Diagnosis & Testing

Accessing Diagnostic Trouble Codes Connect suitably programmed scan tool to the Data Link Connector (DLC) and follow manufacturer's instructions. Clearing Diagnostic Trouble Code ...

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Chevrolet Cobalt Owners Manual. Gasoline Octane
If the vehicle has the 2.2L L4 engine (VIN Code 5), use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving. If this occurs, use a gasoline rated ...