Yet, Another Question

I've asked alot of you guy's and for that I apologize. It's just since I've gotten into AF I have found, thus far, an answer for every problem that I have been having. Please bear with me, here we go:
98' Passport, 211 thousand miles, try to do most of the work myself, but some things I thought were beyond me so I used a mechanic, only to discover that I'm not as dumb as I thought. I had the head gasket changed a couple of years ago and ever since I picked it up and paid the !@#% almost 3,000 dollars the engine has sounded like a diesel. I was told that it was just a sticking lifter, but that it would have no effect on the operation of the engine. So, being the apparent idiot I am, I have driven the thing for almost two years with this sound and absolutely no change in performance. Reading some other forums I have noticed that several others threads are talking about the same problem. Since I'm doing all of this work, and thus far every venture has been successful, THANKS TO YOU GUYS, I was curious if this would be something I could fix or if I needed to track down a "competant" mechanic?
I'm not a complete moron. I have completely disassembled and rebuilt the engine and tranny of a 1975 Datsun 280Z and it runs beautifully!! It's just that between 1975 and 1998 auto companies have added ALOT to cars and dealing with computers makes me nervous, so I've always been hesitant to work on a car with one.:screwy:

You didnt say if yours has the 3.2 or the 4cyl so I'm going to assume that its the 3.2 since its more common. The '98+ 3.2 does not have hydraulic lash adjusters like the earlier ones, they have shim and bucket style valve system so there is nothing to stick. That would rule out sticky lifters. Could be they didnt get the cam shafts timed right which is not good (the 3.2 is a non interferance engine though so wont cause damage). Or they put something back together wrong.

Sorry, it is a 3.2 V6. So, they may have put something together wrong? Should I dig in and re-work the valves?