I got 2 ECU errors, huge power loss. Help please

[240sxfan]

I just replaced my clutch and it works fine. But I've been having error codes for a while, but once I checked it gave me code 55, which means everything is ok, but I still noticed lack of power in my car. When turned it on last time after clutch change, it gave me COdes 34 and 82 which are: 34: Detonation (knock) sensor, and 82 - Crankshaft Position Sensor. I have no clue where they are located in the car. Can anyone please tell me where I can locate them, and buy the sensors? It also seems that I finally found out why my 240sx has felt very weak as of lately. thank a lot!

[NISTECH]

the knock sensor is located under the intake manifold mounted to the block. The crank position sensor is mounted to the bell housing of the trans. did you leave it attached when you removed the trans? little black sensor with a single 10mm bolt holding it in.