my 94 explorer has a bit of a chatter when its at 2500-3000 rpms and thats it, and it seems to me that it will only do that when its warm outside. it runs strong and it has 153xxx miles on it. i was told that it is called catalytic converter chatter from a friend that used to work on explorers alot, and he said that the internals in the converter shrink with causes it to do this. i have no idea about it. Could it be something with the timing chain and if it is, is it a normal type of problem? like timing chain rattle or something. like i said i dont know anything about these things so anything will help. or is it something else that can be fixed. thanks

 

well a chatter is a lil unspecific so its hard to say. but the ohv motor has poor oil circulation in the heads which causes excessive valve train wear so it will sound like its tapping. maybe thats it?