supercharged previa knock sensor signal, resister attenuation for boost lack of power

Finally fixed lack of power issue. Found solution on yahoo previa group old messages. This is my 3rd supercharged previa. first 2 95s did not have this issue. 97 with 70k did. The ECM retards the timing with boost to less than 5 or even retarded -5 range, with resultant lack of power, due to knock sensor signal. No knock or discernable abnormal noise, but for some reason, the knock sensor hears something and tells the ECM to retard the timing to prevent damage to the supercharger. Cant just unplug the sensor since the ECM needs a knock sensor signal or timing gets really messed up.
I changed plugs, wires, fuel filter, crank position sensor, O2 sensor, distributor cap and rotor, PCV valve, mass air flow sensor, all to no avail. Solution is to decrease the sensor input to the ECM via jumping connector wire 6( black sensor wire from knock sensor) on the 16 pin connector, to connector wire 24 (brown ground wire) on the biggest connector. with a 1k ohm resister wire from radio shack. I had problems with just shoving the resister wire next to the above wires as others have done`, so I used red 18-22 splice snap connectors. Used the ecm connector diagrams on Chilton.
Hope this will be a permanent fix but no guarantees. Plan to use premium gas to decrease chance of knocking or pinging, now that the knock sensor signal is attenuated. Supposedly this is a supercharged engine defect that has lead to unnecessary engine replacement in the past.
Scanguage 2 timing values helped isolate the problem to retarded timing with boost, as my boost gage was boosting to 5 psi, so I knew it wasn't the supercharger.
Hope this helps someone else; only took me 4 months to figure it out! Van drives like new now, doubt if the dealer could have figured this problem out or suggested this solution.
!

Also, the van never threw a code. Just accelerated very poorly with boost.

why not just replace the knock sensor if it's bad?

Supposedly must remove engine to replace sensor per factory manual. But that would not have helped since a new knock sensor would do the same thing. It hears what it thinks is knock from the supercharged engine,then retards the timing thus no power with accel., Problem is intrinsic with the supercharged engine, piston slap? Accelerated by infrequent oil changes?

cheap crap gas and carbon build up in the engine
you really should be using "super" as recommended by Toyota... even they said that for the N/A version for full performance, despite the fact that the cheap regular gas is minimum for it
result when using cheap crap gas is pinging, running rich, and lots of carbon build up... it's a downward spiral once that starts... carbon build up = hot spots in combustion chamber = detonation = run more rich

I would carbon clean the engine, then start using better gas... it should improve immensely and likely prevent this issue from happening again

Sounds like SeaFoam smoke-show time👍