Definition of discourse marker noun from the Oxford Advanced Learner's Dictionary
When an engine starts knocking, one of the first things a mechanic will check is the oil pressure. A warning light may come on in the car, and adding sufficient oil will solve the problem. Sometimes, a knocking noise is caused by loose torque converter bolts or a loose flywheel.
Usually, knocking indicates bad bearings on the crankshaft. You are going to have to budget for a rebuild on the bottom end of the engine. If the engine has extreme mileage, you would be better off with a remanufactured engine. Usually, a knocking engine is very bad, and requires replacement or rebuild of the engine. If the engine is going clank-clank-clank at idle, and the sound gets louder â¦ when you get on the gas and disappears for a sec or two when you let off, that means you gotta replace the engine.