Check out my tune. Cant get rid of KR.

[gao8302]

This is my first post here but i have been a member at performancetrucks.net for a few years now. I just picked up efilive and im a noobie to tuning. I cant seem to get rid of the kr im getting when in boost. Is there something im missing in my tune. I have everything in my sig. Also i have not done any autove tuning because i was told to get the kr problem down before i do this. I have included my tune and recent log for you to look at. This Kr issue in driving me crazy so if there is a efilive god then i hope this problem can be fixed so i can finish with the tuning. In the logs the wideband is hooked up to analog 2.

[Goldfinger911]

What about the 7.4 degrees of KR when you were at 944 rpm with less than 10% throttle? Weird.

Bad sensor(s)? Wiring problem? Engine noise? Incorrect knock sensor calibration?

I am no expert on boosted LS engines (however 2JZGTE's are a different story), I just thought that was strange behavior. I am sure someone will chime in with some advice for you.

[gao8302]

[QUOTE=Goldfinger911]What about the 7.4 degrees of KR when you were at 944 rpm with less than 10% throttle? Weird.

Bad sensor(s)? Wiring problem? Engine noise? Incorrect knock sensor calibration?

Thanks what i dont understand. I havent done anything to the knock sensors. I have to get this figured out. I hope someone will chime in.

[hquick]

Just out of curiosity try this.

[gao8302]

what did you change? Do you see anything wrong with my tune?

[hquick]

I just richened your commanded fuel a tad (like...a very small amount) where you were getting the KR.
If you open the original tune and then load this one as an 'alternative' calibration by clicking on the picture of a file with the red arrow on it under 'view' in the toolbar. You can then click on the double ended red arrow to see the differences. If you double click on the items that come up as differences it will open those items.
Ie...open the commanded fuel table and then toggle between the new and old table by clicking on the two pic's of maps which will appear in the toolbar as CAL and ALT.

[hquick]

By the way....I'm having the exact same problem and our setups are almost the same. Mine's a 5.7L.

[gao8302]

I just noticed that. I will load the new tune and get some logs up for you. Thanks for the help

[gao8302]

So you are working on getting yours tuned as well?

[hquick]

Yes. I seem to be having the same problems. I'm fairly new to this also so I can't give you any deffinitive answers as yet. If I can get rid of my KR....I'll tell you what I did to remove it. I'm currently also receiving a fair bit of help from other members here.
Your fuel just looked a little lean at those points.
It might work...might not...but won't cause any harm.

[hquick]

Oh...and if you haven't done the Auto VE yet...I would say deffinately do it.

[BlackGMC]

Do you have a wideband, I did not see one in your sig.. I would suggest doing the AutoVE first and also I would richen up your commanded fuel until you get the KR straightenout. OH and you need to remove some the PIDs next time you log, you really only want to log 26 channels not 30.

[joecar]

You mean no more than 24 channels; upto 24 channels logs at 10 frames/second; 25-48 channels logs at 5 frames/second.

[BlackGMC]

sorry meant 24, I at least got the general idea if nothing else....

[joecar]

No worries. :) I corrected my post (25-48 channels gets 5 frames/sec).

[gao8302]

thanks for the input.

[BowlingSS]

Did you get the KR corrected?

Bill
:cheers: :cheers:

[gao8302]

Not yet. Dc justin told me to check for intake leaks and clean the maf sensor. The weather is to bad at the moment so im just waiting for the snow to clear. I will get a new log up and i hope we can get this fixed.

[hquick]

Mine's pretty much gone...desensetizing the knock sensor helped quite a bit.

[gao8302]

And your sure that your not getting real kr. why are you desensetizing the knock sensors? Did you do anything to burst knock? What was done?


Mine's pretty much gone...desensetizing the knock sensor helped quite a bit.

[hquick]

I zero'd the burst knock.
I was getting KR for no apparent reason so after talking with a friend who writes the Cal's for GM over here I decided to try it.
Also another member her helped me out.
I still get a tiny bit of KR at times....but nothing substantial.

[dc_justin]

And your sure that your not getting real kr. why are you desensetizing the knock sensors? Did you do anything to burst knock? What was done?

I would advise against knock sensor sensitivity changes. Your knock is from running lean while in boost (13.4:1 as I recall). Check over your intake tract first to rule out a leak, if you're still at that point, then it's time to tune your MAF calibration to bring your commanded AFR in line.

Justin

[hquick]

Absolutely listen to Justin.
I was at the stage where I could not find any reason for the KR so I tried desensitizing the sensor.
I'm an amateur so whatever I say is purely from my experience with one vehicle and a totally custom setup which nobody seems to be able to figure out/tune.
One thing I will say about KR.
The US tolerances are alot less stringent than they are here in Oz.
I was talking with a friend who writes the cal's for GM here...and he was saying in the Vette's and Camaro's...they have 'acceptable KR' and it's basically "just make sure it won't blow up".

[ScarabEpic22]

Makes sense Howard, the stock spark maps for the 4.2L I6 P10s usually see anywhere from 3-7* of knock, stock!! Running premium helps a little, but only at high loads (unless you tune for it like me, then its way better anyway :D ).

[gao8302]

I would advise against knock sensor sensitivity changes. Your knock is from running lean while in boost (13.4:1 as I recall). Check over your intake tract first to rule out a leak, if you're still at that point, then it's time to tune your MAF calibration to bring your commanded AFR in line.

Justin

Yes im still waiting to work on the truck. The weather sucks. I will get a log up asap. Thanks again justin for all the help along the way.:D