The Knock sensor is located under intake manifold on Nissan Altima.Its very close to the oil filter.You need to access Intake manifold to remove/ replace knock sensor.
Its a time consuming task.
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The car will not start?
Car will not crank?
Car has no spark?
How to troubleshoot car battery?
How to test starter solenoid?
http://schematicsdiagram.blogspot.com/2011/06/how-to-test-starter-solenoid.html
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How to test cars starter?
http://schematicsdiagram.blogspot.com/2011/06/how-to-test-cars-starter.html
How to replace starter in car?
http://schematicsdiagram.blogspot.com/2011/06/how-to-replace-starter-in-car.html
Its a time consuming task.
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For more car related problem troubleshooting:---
This are the sections, you can go through and click the link to read its troubleshooting.
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The car will not start?
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Car will not crank?
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Car has no spark?
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How to troubleshoot car battery?
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