definetly a spun bearing.... what ever you do DONT "smash on it around the block".... right now repair-wise ur lookin at a machined crankshaft and possibly crankshaft journals or rods needing to be machined as well.... may as well rebuild it while its apart.... if u "smash on it around the block" u will be looking at a completely destroyed engine w/ a hole in the block where the rod ull throw would come out.... check your oil if ur really low i guarantee its a spun bearing.... if u end up gettin it rebuilt and need a mechanic drop me a pm i just rebuilt my entire motor and my friends dohc head....SMoKeM240 wrote:my car did this a few times, its not a rod knock.. when u rev it up and it sounds like its running on 2 cyls right? all i did was smash on it around the block and it stoped.. a spun rod bearing will give u a loud rattle noise threw out any rpm