Rare sound in the Chevrolet Optra Advanced engine

Stimed friends, I have a Chevrolet Optra Advances Model 2009, its engine is the 1.8cc Etec II. It is also known as Laccetti elsewhere, my problems is that I have a sound in the engine, CT, TAC, TAC, TAC, I have been told that I should not worry because it seems to be vavas and that these can be calibrated, but the car is in the 95,000km. Looking on the network I found that this problem could be something that is called the multiple of admination because they are fins that possibly be worn and, that would be noise: I am afraid that something happens to me with another car, of another class that I had, that was a Nissan Xtrail where that sound was actually a piston that was not working poor See this message help me please; In the forum at another time collaborate with the way of placing the 2 sensors that I tell you. Thanks friends.

Hello Ivan.
You have several checks to do:
Verify if you have smoke because it would be a symptom of bad valve calibration, if not, the same valves, check that you have lubrication in all the rockers, with a hose you can try to locate the site where the noise occurs (putting a tip in the sector that suspects and the other tip on your ear) if the thing persists, looks at the bench.
LUCK
MIGUEL