Help with possible Knock issue

Z4fun

Hi,

I have a vortech v3 , stillen kit with top gunz a2a upgrade in my Z. it was originally tuned on uprev for years with 19 degrees of timing on top and no knock and had the stillen 600CC injectors and 9PSI pulley in florida and intake temps around 120 ish summer. Tuned by admin

I switched to ecutek after doing the soho intake relocation and seeing the afr's were getting lean. I re-tuned with admin the car was running fine no knock and 19 degrees on top, but injectors were maxed and startup was not good on SD tune.

Recently I upgraded to 1050cc ID injectors and re-tuned with Seb, the timing is the same but im getting possible knock in the mid rpm range but only sometimes. I can do the same pull twice and once will have knock sensor pass the threshold on one cylinder like 4 or 5 kind of random with each test and the car will pull timing 1 to 2 degrees. I will attach logs and pic.

I would like to know what is your knock thresholds and timing compared to mine, on the dyno its making almost 500 whp.

I'll attach 2 logs please let me know if any ideas, my next step is to add octane booster to test the knock.

Attached Images

knocklow.JPG (358.0 KB, 14 views)

Attached Files

Tests - 1TH1B - 2023-12-02 16-13-10.zip (76.9 KB, 2 views)

Spooler

Do you have a proper set of catch cans? If not, install those and see if it improves.

ByThaBay

What you need to do is run this program on a set of logs covering the entire RPM range:

https://www.dropbox.com/s/ww0pvzp2a6...ilder.zip?dl=0

This program will reconstruct the knock threshold table from within the tune and will show if it has been tampered with directly. There are also other ways to disable or desensitize knock sensors, but based on the data you're posting, I think you're after determining the KS threshold table from within your tune.

In order to determine the factory table, we need to know your calibration ID. If you can post it, I can open the stock rom and post the stock KS threshold table for you to reference. You can then compare the generated table from your logs VS the oem table to see what kind of tampering has been applied.

ByThaBay

let me know if you need help running the program.

Z4fun

@spooler yes I have duel catch cans.

@bythebay , thanks will download it, try to run it this evening and get back to you.

Just fyi, since seb tuned it I dont think I can edit the tune if we find something

Z4fun

Where do I find the calibration ID ?

Z4fun

Yes, please advise how to run this program?

redondoaveb

What did Seb say? Have you talked to him?

__________________
Fast Intentions "Stage Seb" twin turbo #098- Specialty Z/Tial-Xonarotor/CJM/Ecutek/HKS/KW/SPL/Hotchkis/Rohana/Toyo
700+whp

ByThaBay

You must have Java installed. Search "download java" then simply drop your log files into the same folder as the .bat and .jar files, and double click the .bat file - the program will run and will produce a new KS table for you to review.

You can get the calibration id by using ecutek query ecu or using the bluetooth to check "ecu information"

Z4fun

Yes, he said he's not to sure if its real knock and to run octane booster to see if it changes.

I ordered his recommended boostane and waiting for it.

Z4fun

Thanks for the info, will try it when I get home.

Z4fun

I ran the program it created a new file called ks.map.new I attached it for review, thanks again.

I found this Cal ID - #Ecu 1 CALID: 1TH1B

Attached Files

ks.map.new.zip (696 Bytes, 4 views)

ByThaBay

it looks like you ran it on a narrow rpm range only , 1600 rpm to 6300 rpm - if you want a more accurate table you'll want to feed in as much data as possible for the widest range possible.

ByThaBay

Kudos to you for running the program - you've taken the first step to awareness!

I pulled out your data and the OEM knock threshold table then I did the math to calculate the % threshold difference. It looks like within your log data your thresholds show to have been increased on average over 55% with some areas having the threshold more than double the factory allowance! According to ecutek tuning guide here: https://ecutek.zendesk.com/hc/en-gb/...ents/204332925

Given that your thresholds have been raised far beyond the mentioned 5/10% I would give some serious consideration as to why and what risks are being accepted by doing this.

It's not uncommon to have issues with the knock detection system for a variety of reasons and false knock is a real thing. The key take-away here is that the less sensitive (higher threshold) the ecu is to knock, the more likely that real knock will get missed.

Screenshot 2023-12-13 113546.jpg

Z4fun

Thanks so much for your reply! I will run more logs with full rpm soon.

Im surprised because all of my tunes were on dynos and no knock. Also the ECUTEK recommended knock threshold change is that for Supercharged Z's? I've heard from some tuners that they make alot more noise.

If anyone on the forum has a supercharged Z with stillen, vortech, topgunz, SOHO ect.. can you chime on ur knock thresdholds as well please it would be nice to compare. Thanks.