You just wanna make sure your gaskets aren't leaking and allowing everything to run without proper lubrication.

I know the LIM gaskets are a common failure on our cars unfortunately. Hell I had valve cover gasket leaks that I didn't know about until I did my rocker change.

 

My 06 3.5L does the tapping thing once in a while, but it only last a few seconds, and then goes away...its done it since the day I bought it, and like I said, its only once in a while it happens on a cold start up for a few seconds....I would not worry to much about it. Sounds like your case was low oil.

 

Thanks folks I sure appreciate all the helpful info I am getting in here. Yes the oil change and additive really did the trick, so far I have tried to get it to do it again and it hasnt even made one tap sound. sorry for all the trouble, I get to freaking out when Jr is feeling ill. You are right I should keep an eye on my oil at all times. I took Jr out on the back country roads and opened it up and boy it sure is a blast to drive that car is one sweet ride.

 

Sounds like you had a lifter ticking- usually happens when a lifter is starved for oil, due to dirty/too thick/not enough oil. The "tapping" comes from one of the valve covers- top of the engine like you described.

I had the same problem in my Regal when I first bought it. The stealership I'd bought it from had put some dino 10w40 in it, and it was causing a lifter to starve. I ran some SeaFoam through the oil and swapped to synthetic 5w30 and the sound's never come back. This is a fairly common issue with 3800s and L67s in particular. Glad it's fixed for you. Make sure you follow a strict oil change schedule and check your oil level reguarly to keep it from coming back.