2004 Nissan Sentra 1.8 L light tapping noise on the left side of the head ?

My 2004 Nissan Sentra 1.8L 89000 miles makes a light tapping noise when is in idling position [ only sometimes and it depends on how it is standing ] , it does not tap while I'm driving it . I change my oil every 3500 miles . I got a oil change done and also added a bottle of Rislone Enigine Treatment . what could be wrong with it ? and what else I can do myself before taking it in to a garage ? Any [ SERIOUS ] advice is appreciated .
2004 Nissan Sentra 1.8 L light tapping noise on the left side of the head ?
If it is a tappet, they can be adjusted fairly easily (not yourself, get a mechanic) or if it is lifters, add 1L (1 quart) of ATF (automatic transmission fluid) to the oil an hour or two before your next oil change. This will not hurt the engine and with the powerful cleaners in it, it will flush out the lifters.
2004 Nissan Sentra 1.8 L light tapping noise on the left side of the head ?
engine rebuild -or keep driving and ignore - I recommend turning up the radio.
sounds like a tappet or lifter i would use either motor medic or mystery oil it work on my car
on those you have to adjust the valves ever so often so that's probably whats giving you the slight tapping noise your hearing,it wont hurt it to drive it like this but about every 60-75 thousand miles the valves should be re-adjusted to keep this from happening,its not a big issue though but as soon as you can you should get them adjusted,we own one is the reason i know this,good luck.