Some weather and atmospheric conditions can create a chemical fallout. Airborne pollutants can fall upon and attack painted surfaces on the vehicle. This damage can take two forms: blotchy, ring-shaped discolorations, and small, irregular dark spots etched into the paint surface.
Although no defect in the paint job causes this, we will repair, at no charge to the owner, the surfaces of new vehicles damaged by this fallout condition within 12 months or 12,000 miles (20 000 km) of purchase, whichever occurs first.
Chevrolet Cobalt Service & Repair Manual. Intake Manifold, Replace
Removal
1.
Remove air inlet duct and resonator.
2.
Disconnect IAC, TPS and MAP sensor.
3.
Disconnect EVAP and PCV hose.
4.
Disconnect purge solenoid tube and
brake booster hose.
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