The serious version of engine knock. Deep and rhythmic, louder under load. This one ends engines.
Rod bearing wear from age, low oil, or oil starvation.
Stop driving now. Every mile grinds metal. Confirm with a shop before the block pays for it.
Reading about sounds only goes so far. The tuner on our home page listens in your browser and tells you what it hears. The app goes further: it names the exact fault, checks it against your vehicle, and tells you how urgent it is.