Chevrolet Cobalt Service & Repair Manual: Exhaust

Timing Chain, Replace

Caution: With the timing chain removed, avoid turning the camshaft or crankshaft. If movement is required, exercise extreme caution to avoid valve damage caused by piston contact. ...

Catalytic Converter R&R

1. Raise and support vehicle. 2. Remove wheel drive shaft heat shield. 3. Remove Heated Oxygen Sensor (HO2S). ...

See also:

Chevrolet Cobalt Service & Repair Manual. Engine Oil Light, Diagnosis & Testing
1. Understand and validate customer concern. Inspect visible system components for obvious damage or conditions that may cause concern. 2. Inspect for related bulletins, recall/field actions and preliminary information. ...