I just bought a 1998 TL 3.2 with 48000 miles.

Noticed recently when starting up in AM, hear a knocking noise like a diesel. Quiets down after warm up of 5 minutes or so, then I can't hear it at all. Never heard this before I had a mechanic change the oil, some one told me only the OEM filter should be used.

Mechanic did plugs, cleaned throttle body and changed all fluids.
Said the valves on this motor are self adjusting.

Car looks like it was taken care of, but who knows.

Any ideas, I've got 45 days left of the used car warranty.

Thanks

Jc