Nissan Repair/knock in motor
I emailed you a day or so ago you said that I should have a scanner put on it don't own one so I was going to take it to a-zone but knocks pretty loud like a main bearing or something if it was a bearing would that make the ser. Eng. Light to come on? Or does my 1.8 L. Nissan Sentra have a anti-knock sensor,and do they make your motor knock if they go bad? I afraid to drive it to far.
The engine knock could be caused by several things:
Low quality fuel
Slipped timing belt
Usually engine bearings do not activate the engine light. If it is knocking bad yes I would not recommend driving it. Assuming it is not one of the above, you can actually purchase an OBD reader for maybe $30. Will be a good investment.
As mentioned once you get the code I can assist you further.
For now though have the items above checked and link