Buick 2004 Century - Manual (Page 247)

10. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.
11. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the HOT
mark when the engine is hot or at the COLD mark
when the engine is cold.
Power Steering Fluid
The power steering fluid reservoir is located at the back
of the engine compartment, on the passenger’s side
of the vehicle.
See Engine Compartment Overview on page 5-12 for
reservoir location.
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