Help. Can't get rid of knock :(

[MadMaxHSV]

Tried a few more things to eliminate some possibilities.

- Changed plugs from platinums to coppers (heat range 6) to ensure plugs weren't causing the knock

Log here shows a run after the plug change. Log_P15RSX_0020newplugs.efi Same situation as before

- Pulled 3 degrees across the timing map (map already quite retarded)

Log here shoes a run after the timing change. Log_P15RSX_0021newplugslowtiming.efi Same situation

Unless something else in the cylinder is getting a hot spot. Thinking false knock.

Joe, out of interest, what makes you say it doesn't look like real knock.

If it is false I guess its likely a resonance thing that something is rattling around those load areas.

[joecar]

Reduce your pid channel count to 24 or less (reads frames from PCM at maximum sample rate, 10 Samples/second), this will show a clearer picture of KR.

I see very small KR (1° or less) very infrequently, looking like a single short pulse, and not corresponding to any load/airmass increase, so it leads me to conclude it isn't knock related.

[odd boy]

r u sure there is no vibration around the knock sensor? or any object hits the block??

[MadMaxHSV]

Jeez start looking and you find lots of hidden issues.

- Knock sensor loom had fallen onto the headers (now strapped back)
- Slight exhaust leak from one header gasket (bolts re-torqued)
- Track-rod ends sound FUBAR'd. Rack knocks when jogging the steering
- One header branch is sitting hard against a nodule of the block (won't budge so can't see it knocking though.)

Returned the timing higher slightly again and reran after strapping the loom and torquing the headers. Still there.

Does come on under acceleration but if constant with the throttle (keeping it down) pings once then stops. Bleeps a few times if off/on slightly. log attached Log_P15RSX_0023.efi (still look like false knock?) I'd already upped the recovery rate hence it ramps back quite fast.
Gotta be something rattling.

Will attempt to address the issues above and try again.

[madmax4499]

what did you end up finding? is that little KR even worth worrying about? when or how much KR is bad?

[J.Abbott]

If this is a LS engine, you are getting oil ingestion. Check your PCV and then install a catch can. Good Luck

[MadMaxHSV]

Latest update is its still there, but minor. WOT on the dyno there was no KR at all.
Largely ignoring it for now. I've tried bringing PE on earlier which seems to have made improvement but could be placebo effect as the KR was showing up in the logs under PE before.

I've already got an altered PCV system with catch can so the heavy oil ingestion of the original setup is gone, this isn't the issue. Cleared up a lot after I rebuilt the motor anyway with better rings.

[J.Abbott]

Where are getting the KR at, 4K

[MadMaxHSV]

Usually get it at half throttle between 3-4k

[J.Abbott]

So it is happening at pretty much peak torque. What is the timing right there and what is done to the engine. Also what g/sec on the cylinder are you at when it is giving the KR.