Before leaving the vehicle, fully press the clutch pedal down, move the shift lever into R (Reverse), and firmly apply the parking brake. Once the shift lever has been placed in R (Reverse) with the clutch pedal pressed down, the ignition key can be turned to LOCK/OFF, then remove the key and release the clutch pedal.
See Manual Transmission Operation.
Chevrolet Cobalt Service & Repair Manual. Heater Hose, Replace
Inlet
1.
Drain coolant into a suitable container.
2.
Loosen hose clamp connecting hose to
heater core inlet tube.
3.
Loosen hose clamp connecting hose to
water pump bypass tube.
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