2002 toyota solara convertible 3.0 v6 loud rumble for 4 second on cold start up

rockandroll

On initial startup in the morning especially or if the car sits for an extended period there is a 4 or 5 second rumble that sounds like engine or manifold leak but both checked out good. Goes away completely till it sits again. Bought the car 2 years ago and didnt notice anything, Is in excellent shape has 90000 on it. Had it checked by many mechanics but they cant find anything. searched the internet and someone referred me to a TSB 0094-09 that talks about some intake gear that is operated by oil pressure and that if it is leaking back into the oil pan. It says thatthis gear changes the various cam shaft positions for power. Sounds strange , If it doent get oil it gets loud until it does. Anybody help

PF_Flyer

Since you mentioned it, maybe the cam position sensor has gone a bit wonky