That's good. You hadn't specified so i just wanted to make sure. The 3.5 did make a light, almost muffled ticking/tapping noise that was always there, but it did not get louder at higher Rpm. Have you noticed any loss of power since the noise started? It's possible you may have thrown a rod. That would be a tapping that would be more noticeable at higher rpm. A good service department can easily diagnose this with a listening tool that is kind of like a doctor's stethoscope. Hopefully that is not the issue, as the usual course of action is either to completely rebuild or replace the engine
Hmmm, I would definitely check the timing belt and tension, if I'm not mistaken the 3.5 had a belt rather than a chain. If you haven't had it looked at before it would be high time you get it replaced.
