Buick 2013 Encore Owner's Manual page 314

11-6 Service and Maintenance
(2) Check all fuel and vapor lines
and hoses for proper hook-up,
routing, and condition. Check that
the purge valve works properly,
if the vehicle has one. Replace as
needed.
(3) Or every four years, whichever
comes first.
(4) Or every five years, whichever
comes first. See Cooling System on
page 10-11.
(5) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(6) Or every two years, whichever
comes first.