Silicone grease on weatherstrips will make them last longer, seal better, and not stick or squeak. Apply silicone grease with a clean cloth. During very cold, damp weather frequent application may be required.
See Recommended Fluids and Lubricants.
Chevrolet Cobalt Service & Repair Manual. Valve Cover Gasket R&R
1.
Remove the intake manifold cover.
2.
Remove the air cleaner outlet duct.
3.
Disconnect the intake (3) and exhaust
(2) camshaft position actuator solenoid valve electrical connectors,
Fig. 1.
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