You just answered your own question, its the exhaust, not ropey rings/pistons. Theres something in the exhaust blocking the spent fumes from getting out and suffocating the engine!!
Carbon buildup either in the cylinder head or in the muffler itself. Try a new/different muffler first. If it doesn’t help then the problem is probably internal.
You might need a new muffler.
could mean your muffler is cloged just get a new one and see if it helps
You just answered your own question, its the exhaust, not ropey rings/pistons. Theres something in the exhaust blocking the spent fumes from getting out and suffocating the engine!!
Carbon buildup either in the cylinder head or in the muffler itself. Try a new/different muffler first. If it doesn’t help then the problem is probably internal.