if that ticking noise increases with rpm that may be lifter noise. it happens when the lifters are not getting they lubrication it need. it may be due to "dirty"/contaminated oil and or in some engines it would indicate time to adjust them.(if they're mechanical) My Opinion This noise is sometimes also cause by your oil type. since your vehicle is over 10yrs old there is some wear in the engine. if you are still using 10/30 oil it may not be enough to provide the cushioning your lifters need to prevent metal to metal contact. what i do is i change my oil to a thicker type.(20/50) this provides additional cushioning.In a '''NEW''' vehicle this may not be recomended.In your case we are speaking of 10yrs of service and wear in the engine WILL occur. your manufacturer specified oil applies to new vehicles since obviously there is no wear in the engine they don't need the extra protection/"cushioning".
Faulty engine
ticking sound in engine is usually not caused by a timing belt ticking is usually caused by worn cam shaft or clifters most cars now have hydraulic lifters. if oil is low it will cause ticking. if a lifter is worn it will cause ticking these should have been ckecked for wear when replacing timing belt
Ticking in an engine generally refers to the valves. If ticking is apparent on a 1994 Chevy Lumina tighten the valves to factory specifications.
Normally loose tappets will cause a ticking sound in the engine. Depending on if you have mechanical or hydraulic tappets you may need to have them replaced or simply adjusted.
Detonation...Needs to be fixed immediately or will eventually destroy engine.
The most likely cause of a ticking sound in a motor is a bad timing belt. A valve out of time can also cause a ticking sound.
a "knocking" noise could be your lifters. and the ticking when accelerating and letting out of the gas is the same thing. check your oil and if it's full then you may need to think about either having them adjusted, or getting new ones. depending on what you have depends on whether or not you wanna sell it
Collapsed hydraulic valve lifter? Rocker arm (valves) need adjusting?
Could possibly be a bad lifter.
Stuck hydraulic lifter.
collapsed lifter?
can you elaborate? engine noise? stationary/moving? ticking, tapping or a definite knocking?