Fatigue, maybe from missing or broken hangers.
cracked water jacket in the head
Answer It could be that you need a new muffler. After so long the baffling inside the muffler can burn out. Also make sure that the muffler is not cracked or that exhaust is not leaking before it gets into the muffler. At the gasket between the muffler and the engine. Hope ths helps.
Bad head gasket?Cracked block?
Do not drive this car. Repair immediately. Blown head gasket or cracked head.
defn cracked nipple
Your bad muffler might be part of the reason your check engine light comes on. Usually, your bad muffler causes something else to go wrong and that causes your check engine light to come on. Problems cascade.
loud, and shety muffler
A hole in a muffler is from two causes. It has either rusted through or been damaged by something hitting it.
leaking or cracked manifold
A cracked/warped head, Blown head gasket, cracked cylinder wall, or cracked/warped intake manifold.
hotness
a cracked gasget could cause that