1994 engine knock

[Donlawl]

I’m helping my friend with his 94 leaf legacy wagon. Has a loud engine knock which occurs and persist once the engine gets up to operating temp. Has a check engine light on and also will die if you dump the gas pedal from a stop. Knock seems to be coming from the center of the engine

 

[Anthrax33]

Unfortunately sounds like a piston rod bearing has gone bad and the piston is loose on the crankshaft causing a knocking sound.