i made the seemingly all too common oops of shifting fro, 3 to 2 ... it wouldnt idle cold for a while and the valves clattered a little...then it just kind of fixed itself...i think the valves r still making too much noise...i had it hooked up to a computer and everything checked out...would a comp test even read that kind of problem

 

maybe you just need to adjust the valves
You should have a leakdown test performed at the same
time as well as a compression test