Does anyone have a 'Knock sensor' for a 3sgte, or 3sge?  (not sure if they are the same part no. though).
Does anyone know the part no. for one of these? 
 
When rebuilding the engine, I accidently cracked the plastic bit on the knock sensor.

 
 These are the numbers I can see.  04075, & 66014 on the other side.


 
 

Does anyone know if knock sensors can be repaired? Wire is broken in plastic bit.

You can, but its generally not worth it.
 
That is either one of two Vacuum-switching valves attached to the intake manifold.  One is for fuel pressure when hot, the other actuates the TVIS setup IIRC...

Thanks Graham.

I'll have a look tonight, possibly have them both

dwyer125
I'll have a look tonight, possibly have them both

Thanks Matt, let me know... please!

I had a look last night, I couldn't find either, I wrecked a gen 2 engine and I find it hard to believe I would have thrown anything away, I found the intake manifold but the valves were removed.
I'll have another look when I can.
I would have thought many people would have the vacuum valve as many have put gen 3 heads on their gen 2

Just plum it to stay open it will be okay as I know you are increasing the boost with no waste gate creep. You will lose very minor torque down low. You only need it running with standard boost with waste creep.

Anyone have a knock sensor??

Buy one new.
 
Or, buy the ATS Racing-modified one from a random Chevvy and use that.