Unusual knock.

[Yortt]

Attached is a screen shot of a stationary vehicle log it is a nissan FJ20T 4 cyl engine with wasted spark NVRAM/808/12P/4cyl factory memcal with knock board.
Has anyone seen this unusual knock pattern before, or what may be causing it.
Thanks

[The1]

not tip in bump spark retard?

[Yortt]

I dont think so because while the sreen shot put up is relatively short there are much longer time periods of knock indicated elsewhere in the log which are much longer than the tipin /bump spark settings in the tune will allow. I will try moving those to see if it makes a difference.
Thanks for the comment.

[antus]

What knock board are you running and how did you tune it for the fj20t?

[Charlescrown]

I ad a very similar problem which turned out to be a faulty knock board. At idle it would generate a knock signal.

[Yortt]

What knock board are you running and how did you tune it for the fj20t?

Thanks to those that have responded.

Antus,
I have tried three memcals
1 - Camira memcal … Chip 16057752 & 16057753…1U5059 Kr board..SST27SF512 memcal setup
2 - Sunbird memcal …Chip 16075459 7 16075460…..1C9091 Kr board… SST27SF512 memcal setup
3 - Standard Memcal…. Chip 16075459 7 16075460…..1C0287 Kr board…tsd chip NVRAM setup.

This is the short version the long one runs over many years.
I used 12P-V111-isuzu-fixed.bin and adjusted and tuned it with 12P- V111 XDF.
Upgraded to 12PV-112 and continued to tune until I realized the bin file needed upgrading to 12PV-112 also .
Went back to the un-tuned 12P-V111-isuzu-fixed.bin and upgraded to 12P-112 it with OSE enhanced
Then copied all my additional tune settings from 12PV111 to 12P-V112-isuzu-fixed.bin with Tunerpro “copy selections from right to left function”
The KR issue is basically the same with the 3 memcals used with a Camira PCM with NVRAM and a manual VR PCM with the memcal set up. Car starts idles well revs cleanly at a standstill drives good however has a miss at around 5800RPM feels like electrical have not chased that one up yet.

[antus]

Ahh right well the knock filter is an audio band pass circuit and has to be setup for the sound of the knock in the engine. I read the bore makes the most difference but as the fj is a very different engine i hate to say it but probably all bets are off for knock filtering.

[Yortt]

Hmmm does not look good!

[slewinson]

What about Festy's adjustable knock filter?

Simon

[Yortt]

What about Festy's adjustable knock filter?

Simon

I have one of those which I calibrated for an FG XR6T falcon I did get it close but it was still no where as accurate as the factory calibrated knock sensing (which is now available) not because of the festy's unit but because of the difficulty I had getting a reference point to calibrate it off.
My intention is to run 25psi with E85 on the FJ20 and the whole purpose of persevering with Delco is for its ability to accurately determine the knock threshold which has been in doubt.

I started with Kalmaker which would not run it at all, then went to code59 drivability in low rpm was extremely poor and I could not tune it out, the top end was good and if I remember correctly the knock detection worked fine.