I have a 2003 Auto and lately I've noticed a problem with my engine. For some reason ONLY between 1800-2000 RPMs my car makes this grinding noise like an old car, it sounds like pistons. It almost feels like its hesitating. Before or after that RPM range, the car is fine and I don't notice anything misfunctioning. Car uses Synthetic Oil and Preium Gas.
Odometer reads about 65K.
What could be the problem? Any ideas or has someone dealt with this before?

 

check your oil level. Sounds like it may be the timing chain tensioner. Either way, check your owner's manual to see what your powertrain warranty is. Might still be covered.

 

No, I'm not under warrenty anymore thats the whole problem.
It does the same even after an oil change.

 

sound like a rattle? If so, it's probably the tensioner. I've never changed one though. The rattle comes from either the tensioner going bad or low oil.

 

Ok, but if its a tensioner, how come it makes that noise only at those certain rpms?