Hey, car is -00 S-Type 4.0 v8. It makes strange sound when accelerating, its like something is loose. Sound appears only when in gear and accelerating,
as soon as i lift my foot off the throttle, sound stops. Mechanic tried to check where the sound comes from, and told me its coming under the flywheel.
He told me i have nothing to worry about, there´s just a little rock or something making that noise. Car drives good and smooth, transmission is working
nicely, but really could that noise be something i should not worry about? No fault codes at OBD test.

 

Check to make sure starter gear is not hitting the flywheel while engine is running.

 

could be a bolt comimg loose...I would check further

 

also check the engine mounts.

 

Check the torque on the starter mount bolts.

 

If a torque converter to flywheel bolt is loose or missing the noise will get louder as engine speed and load increases.....been there