What could be causing a 2005 grand prix with 14000 kms to have ticking sound that does not increase with RPMs it seems worse when engine is warm and poor performance especially at low speeds and RPMs?

VALVE LIFTERS... the fact that the ticking does not increase with rpms rules out valve tapping or worn piston pin but is indicative of the bearings going bad in the water pump which also would explain the loss of performance.