can the knock sensor just fail out of the blue? i have a 1995 legacy 2.2 in a 1998 outback the car drove perfectly normal last time i drove it and this morning when i tried to take it to work it had no power and a p0325 knock sensor code that if i erased would come right back.

Edited August 14, 20187 yr by sirtokesalot

Yes they will do that.   Just make sure you get the bolt started by hand so it's not cross threaded and the sensor points back into the lower section of the block.

It retards your timing so low power and poor gas mileage.

yep i grabbed the knock sensor from my friends 2001 parts car and re pinned it into my old ones connector. it was a one wire knock sensor like the one that came off. problems fixed.

Problem is NOT fixed. The 2.5 sensor has a different connector because the 2.2 and 2.5 use different piezoelectric crystal frequencies and it will not correctly identify knock events. It has the right resistance to make the ECU diagnostic subroutines happy but it will not function the same and may lead to detonation and a premature rod bearing failure. Subaru engines are very sensitive to detonation. 

GD

well i ordered one on ebay. i tried.

Learn something new each day!

Incidentally, the kock sensor frequency is mostly determined by bore size. 

GD