Have an engine noise that sounds like a lifter noise. Has anybody had any problems with these kinds of noises? I know this a very vague description but I looking for some opinions and possiblities. This is on a 99 SE with 47,000 miles on it. Sounds like it's coming from passenger side top of engine. Had it to the Nissan garage and they said it was definitely internal and told be to try some BMG oil additive. Since it's the engine it should be covered by the factory warranty. Additive isn't going to solve the problem. Taking it to another Nissan garage tonight. Any help is appreciated.

Thanks
Jim