I see alot about the 4th gen knock sensor being replaced but, I am not sure why people are replacing them. I know on the f-bodys if you replaced a LT-1 with a LT-4 knock sensor there was a power increase..is this the case with the Maximas also?

Thanks

 

I replaced mine because the ECU detected a fault/malfunction with the knock sensor. Therefore, with that fault, the ECU will compensate for the knock sensor not functioning and drivibility suffers. I don't know of any performance enhancements to replacing it. The engine just runs like it should with the new sensor.

 

The knock sensor is simply prone to failure in our case.
The problem is that it's not immediately apparent, but we end up losing significant HP and mileage.
I can only imagine that the LT-1 to LT-4 swap meant that LT-4 was less sensitive, and the ECU had more "room" to try to optimize.
Sentras seem to have a KS relocation trick to a less sensitive area to free up a few HP