Knock Sensor
 

I have had an intermittent CEL coming up on my Version 5 Type R. It comes on cold or hot but usually on the overrun ... when I get back on the throttle it usually goes off.

Anyway I've done a manual fault code read which gave 22 [knock sensor] ... I’ve reset and it came back again.

I'm assuming the next step is to replace?

Where’s the best place to source one and how much am I looking at? My local Subaru Dealers [Tiley Bristol] quoted £70 for a standard UK turbo replacement but couldn't confirm if it is the correct one for my car.

Are all the knock sensors for the classic model the same?

Try E-bay, think they are about £50 new.
I swoped my sti 3 knock sensor with a sti 2 one to eliminate it from a fault i was having a wile back and its exactly the same, cant see them changing to much.
someone will give you a def answer very soon on here i think.
Good luck.

V5/6 is a different sensor, and has a different plug to V1-4

Its worth re-setting the ECU before you change it. I had knock sensor code after changing fuel pump. Ordered it from subaru, but reset my ECU first, and the faults not come back after 6 months or so.
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I've already done an ECU reset ... the code came back after 5 minutes.

Sounds like the V5 is a different sensor/plug?