The most unfortunate thing is that I just started learning about automotive over the summer...I don't know near enough about cars to be able to do any of this myself. They did replace the lifters apparently, put in roller rockers...

The rapid clicking that occurred when I pushed in the accelerator is fixed. There was an exhaust leak, one of the plugs on the side blew off while I was driving, that was the loud thud that I heard: the plug shooting off into the engine compartment. I got another plug and screwed it back in tightly, and the noise went away, however the original clicking, that was supposedly caused by the bores not letting enough oil through to a lifter, still occurs. I poured some seafoam in the engine last night, and I'm gonna run that through for about 100 miles, then change the oil. Hopefully that will work. As for inspecting and tightening the lifters...well, I've never opened an engine before, I wouldn't even know where to start. heh.

even new lifters can have problems and should be inspected before installation. I bought a set of retro roller lifters from comp cams and found one that would not plunge the full stroke and I'm sure comp has a quality control system in place. They sent me a replacement in the mail the next day but it just goes to show you what could happen. If installed the lifter could have stuck on a down stroke causing a tapping noise and possibly a miss. Your mechanic should have found and resolved your problem right away.