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.
Will your car run bad and make loud knocking noise if there is water in gas tank? Why is your gas meter making a squeaking noise? There can be many reasons why a gas meter is making a squeaking  noise. If the noise is accompanied by an odor of gas, you should  call the gas company right away. In many câ¦ases the noise is nothing  to be concerned about, but it can be annoying.