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Circuit/System Testing

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Test the thermostat for correct operation. Refer to Thermostat Diagnosis .
  2. Test the engine cooling system for overheating. Refer to Engine Overheating .
  3. Inspect the water pump and coolant flow for correct operation. Refer to Water Pump Replacement (LU3)  or Water Pump Replacement (LMM)  or Water Pump Replacement (V8) .
  4. Inspect the engine for worn/leaking/cracked cylinder heads and engine block. Refer to Coolant in Combustion Chamber and Coolant in Engine Oil .
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