Is it possible to have audible knock....

[kllrvet]

Is it possible to have audible knock, and not have the knock sensors pick it up? I have attached a link to a scan that shows very little knock, but I swear I heard a LOT more that it shows.

http://www.hptuners.com/forum/attach...1&d=1157975485

Thanks,
Tony

[EC_Tune]

Yep, you probably need to increase the sensitivity (decrease the value in the table) to pick it up.

[jimmyblue]

I have been hearing little bits of ping but not seeing it
show up in the logs when I go to chase it.

If you have engine mechanical noises that are out of
phase with firing events (perhaps synchronous, but
not in the un-blanked interval that the knock sensor
systems use to squelch non-ping input) you may hear
sounds like pinging and see no detects, because it is
not in the expected relation to an ignition event. So
too, actual detonation or preignition may not be seen
because it might be outside the window. Depending on
how the system is set up and dialed in. A system that
is highly discriminating is better at detecting true fast-
burn, over-advanced trouble but more prone to reject
out-of-character goings-on (which arguably have not
much to do with spark manipulation anyway).

But I don't know any deep details of the modern GM
setup.

[Russ K]

I assume the car is boosted. The AFR is very lean below 5000 rpm. You need to log commanded AFR and Maf Freq. Did you change the knock retard rate?

Russ Kemp

[kllrvet]

My car was originally tuned by a shop that sold out and moved. It was tuned with LS2 Edit. The people who took over the shop told me I needed to get my car converted the HP Tuners, so they could install the MAF patch.

After about 8 hours of attempting, the could not get past the auto lock in LS2, and were unable to load HP Tuners. I sent an Email to Carputing, and found out what was needed to reinstall my stock tune and then overwrite whatever was needed. Seeing that the new shop was unable to complete such a simple task, I dedcided to keep them far away from my ECM.

I found someone else who was to copy and paste my LS2 tune to HP Tuners, and also install the MAF patch. He did the copy and paste, but somehow overlooked the patch.

I had enough with depending on others, so I purchsed HP Tuners, and I am trying to get the hang of it, so I can properly tune my car. I have seen from the datalogging, that my car is WAY out of wack, and feel lucky I haven't holed a piston.

soon enough, I'll have the car where it should be.

thanks everyone for the advice, comments, and help

Tony