checked the plugs and re gapped them. The plugs looked nice and clean light gold / brown. didnt have time to swap back to stock pulley

Yeah for the TPS mod you are fine if your idle is BELOW .75v. I did the mod and I think my idle is .60 so you should be fine there.

It'* strange that it doesn't pick up knock when you can hear it but does once you let off the gas. It'* especially strange because assuming your timing is not insanely advanced (which it looks normal) with a wicked lean condition (which also looks normal), detonation only comes under load. Even then you're more likely to see detonations
evil(er) brother, pre-ignition.

A knock sensor listens for a specific tone. If it'* given that everything is in excellent shape from the PCM to the knock sensor (and the knock sensor isn't too tight or loose), I suspect you may have something rattling at just the right frequency to set it off. It'* possible that while under load you can hear it better but free revving creates that certain tone. Some SII guys use a sound barrier on their transmission and around the knock sensor for just that kind of issue.

Maybe try revving it in neutral (don't go too far!) and see if you get a few degrees of KR that way. Another way would be to take it up to speed and manually downshift it. You could take that a step further and tap the gas a few times while slowing down just to jolt the car. If you get KR with either of those you should spend some time checking that everything is bolted down tight and nothing is banging against the block/trans. If you don't get any knock then definitely try the stock pulley and see if that hushes it up.

Just a thought..

To my knowledge the knock sensor sends the signal to the prom and the prom relays that info to the computer and then the computer is what tells the engine to change the advance / retard. correct me if I am wrong.
I still think that the prom is screwed.

anyone ???

Yes, the knock sensor does that.

No, I don't think there is a problem with your prom. My guess is probably something else.

what I am saying is, if the prom is what relays the info to the computer then maybe the prom is screwed. causing a delay between the knock sensor hearing the knock and the computer retarding the timing.

b