Q: Engine knock, is it totally broken?

asked by on November 03, 2015

I'm pretty sure the engine in my 2010 Nissan Sentra is completely broken. It's been knocking for a month now and when I went to start the engine this morning, it sounded like a lawnmower driving over wine glasses. The knock was very severe yet the car is just under 45,000 miles! At this point, is there anything that can be done?

The engines in most of these cars are pretty noisy on start up and quiet down after a few minutes of running. If your noise is an engine lower end knock and not a lifter noise, or if the noise does not go away after a few minutes, then you have other internal engine problems like main or rod bearings or piston slap. The engine noise would have to be inspected to by a trained technician to determine where it is coming from. Nissan will not honor any engine warranty without proof that the engine was maintained with oil changes at the intervals specified in the owner’s manual (or earlier) using the recommended oils.

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