Tapping noise

[S2KFTWkthx]

Alright, so i've done some searching and (to my knowledge) there isn't anything addressing this particular sound. 75k miles on an '02. Oil changed every 3,000 miles, diff and tranny about every 12.5 using pennzoil synchromesh for the tranny and mobil 1 75w-90 for the diff.

I started her up and she idled fine, no noises or anything strange at this point. As i started to get her moving, however, once the rpms got over 2k, a very pronounced tapping noise came from the engine. I took it VERY easy, and found that the noise goes away when RPMS drop back to idle. To describe the sound, while not trying to sound silly, it sounds like "Tick-a tick-a tick-a tick-a" and the noise's speed follows rpm. I checked the oil to make sure that wasn't it...

I've read that this noise could either be the TCT or a broken valve retainer(which is a possibility, considering i over-revved it about 4 months ago, a 3rd to 2nd misshift, much to my dismay)

What's puzzling is that everyone i've known whose had issues with their TCT had the noise at idle as well, which seems to illustrate that the TCT probably isnt the culprit here.

I appreciate all your input.

[repiv]

I take it you've got no CEL or you would have mentioned it, right? Have you tried listening to various parts using a stethoscope. You can rule out the TCT even if it doesn't make an audible sound at idle. Can you duplicate the ticking from under the hood when you increase the rpm using the throttle plate lever? If so, you stand a better chance of hearing it if you are at the engine. 4 months is not an unusual amount of time for damage from an over-rev to finally show up as a discernable symptom. There could be valve train damage or even cylinder/piston damage if a piece finally cracked off. I think it would be wise to do a compression and leak down test. However, a cracked or sunken retainer may not contribute to bad compression or leak down, if the valve is still being held in the closed position. Only by inspecting each one, would it be truly known for sure.

[S2KFTWkthx]

as crazy as it sounds, when i started my car today the noise was gone. Couldn't duplicate it for the life of me.

No, no check engine light or anything... I'm going to take it down to a local shop to get the valves inspected and whatnot, and do a compression/leakdown test. I'm kinda glad it made the noise, rather than just up and exploding, so now i can get it taken care of before any further damage is done. I'll post up whenever i get all that done.