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Discussion Starter #1
The Lexus guys figured this one out, the dreaded P0330 means one of two things on a 1MZFE engine: the signal wire from the #2 knock sensor is shorting to ground due to wear on the wiring harness stuck in the vibration and heat in between the heads AND/OR the sensor is truly bad. The former is often the case and since its at least a couple hours to get to these sensors or the harness people would like an easier fix.

The sensor merely takes a 5VDC signal from the ECU and adds a small AC waveform to it in event of a specific vibration; the sensor is a piezoelectric microphone. this little AC signal is hightly succeptible to noise, thus the shielded wire Toy used on the harness. This puts a tube of grounding all around the 5V signal wire so its incredibly easy for it to short as it ages.

Of course the car still runs after throwing this code BUT it runs with maximally retarded timing and no O/D so its a gutless sled. If you only get one knock sensor code : P0330 or P0325 there is a quick hack to avoid the code ruining your day.

Remove the glove box, pull the ECU connector from the knock sensors (E11 on Gen4 1MZFE) and splice the good sensor wire output onto BOTH ECU inputs, leaving the bad sensor wire floating:
284973


its a bummer to cut wires but once the other sensor goes re-splicing them will be a minor chore compared to the full overhaul you have to do :)

a modified DIY is here, I'll be doing this tomorrow and will report back!
284974
 

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Discussion Starter #2
surgery went well. I opted for a crimp barrel, but also tinned up the stripped leads with good Pb solder so the barrel holds better

Wires were both clear (in the middle) but red sleeve was on (bad) knock sensor 2.
Sleeve moves so be careful no to lose it after cutting!
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Both wires get cut, then tied the two connector side wires together
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the good sensor (1) gets tied to these with a shrink tube on the splice AND on the end of the bad 2 sensor wire.
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As far as I can tell the Gen 3 wires are as follows
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If the Mr2 1MZ-FE swap crowd are correct. I'll drive car hard for a couple days and then reinstall the glove box...
 

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Nice DIY on the workaround!

I added this to The Sticky.
 

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Discussion Starter #4
Car runs strong, no more P0330, I'm putting glove box back on!

I hope knock 1 functions for a good long time!
And I also hope this serves others who encounter one bad knock sensor circuit on 1MZFE!
 
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