5mge Knock sensor wiring

[_gear2]

My mx73 has started shooting the engine code 52 ( Knock sensor signal) and after actually looking under the bonnet it would seem a previous owner (my mate) at some point in time has rewired the the wire running to the knock sensor. I am assuming that the wire needs to be shielded as per this thread http://www.toymods.org.au/forums/tec...ire-4agze.html. Which currently it is not. Though one thing that is baffling me, is the check engine light will only come on if the cars revs goes over 4k shouldn't it come on straight away or could their be something wrong with the ecu? Also the wire is only connected with a spade connection direct to the knock sensor I looked on toyodiy http://www.toyodiy.com/parts/p_G_198...PGFQ_8401.html is part 93385‑16025 the right fitting cap for the knock sensor? and are these some universal standard part that I can get from somewhere besides Toyota. Was told it would be over 2 weeks to get this part from toyota?

[Daddio]

Yes, knock sensor wires should be shielded (and the shielding earthed at the ECU end)
Only getting a MIL after 4k rpm suggests the sensor is 'hearing' knock rather than an actual sensor fault.
As a hint, make sure plugs/leads are clean and good (no oil from leaky gaskets!) as oil/water/dirt can cause this symptom (well, it did for one of my 7M-GTE's, cleaning leads and replacing plugs fixed the issue)