If you go back to the stock MAF freq table for whatever reason or change the one you are running, you need to work on the MAF correction table all over again. Think of the MAF freq table as the base, and the correction as.... well...the correction for specific loads & rpm's.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
ok... so it isnt like nudging one a bit totally screws the other.... but a change to the freq should be followed by a tweak of the correction...
Sounds like the frequency table is like rubbing compound... to get the dirt and scratches out of your dull paint... and the correction table is like a good wax... to shine up and polish and restore gloss.... if you dont have dirt and scratches, just a wax should get ya looking pretty. But if you need to rub it out... you will need to re-wax after.
but there should be no need to ever have to strip back to primer (stock tables) unless you somehow majorly screw up and need a clean slate. right?
Right, unless you change the intake tract a bunch, like a different diameter, design, ect. Our MAF sensors are very touchy to say the least. Just a K&N Drop in filter changes the fuel trims 5-7% IIRC. Airbox mod was 2-3%, AEM CAI around 8-10% and the Hahn I'm running now is about 12% different than stock in spots.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
I'm following the guide exactly, and my WOT MAF tuning is near perfect, but I'll be damned if the mid-low range of air flow doesn't get worse every time. Any thoughts?
Mine will vary a few percent in the midrange with each log which is why I log all week, look the averages over and make minor changes. I haven't touched the MAF correction for about 2 weeks and it will go from -.8 to +1.6 during my 40+ mile commute. With the Hahn intake, it will always go a few points positive during accel and a few points neg on the decel. Depending on weather & traffic the averages will change a bit.
Try and ignore any cells with less than 50 hits on your STFT+LTFT histo and make minor changes manually keeping the cells relatively close to the value in the cell next to it, no drastic jumping around cell to cell. Smooth transitions.
The trouble with using the paste special cheat is that you may be correcting cells that only had a hit or two during a hard accell and skewing the avg for that cell all out of whack. Persistence!
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
I actually think it may be related to DFCO or something, I'm legitimately seeing areas with 60+ % error and correcting those will make the error go up. It's in the 1500-2200hz range that shit gets wacky.Originally Posted by Iam Broke
Which is where you are freq wise when stopping & starting out all the time. It took me months on the Hahn CAI intake to keep it from going +5 LTFT's in stop & go traffic.
I have no idea of your mods, if any. Sounds like you are way out of the ballpark or have a serious boost/vac leak.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
Bone stock Sky RL. No boost/vac leak that I'm noticing. Gonna look around my logs some more and see WTF is going on. Especially since it worked fine for WOT tuning, I ended up with <1% error there.
How do I make a Custom PID to add the LTFT's to the STFT's I have the histograms I'm just too dumb to make the pid's work.
read thru the scanner section and it will tell you how to set it up.
Just curious and not sure if this has been mentioned before but here goes; If after my LTFT's are dialed in as best I can and I move on to working the MAF correction and the LTFT's drift a bit, is making any changes to the MAF freq. table going to affect any changes I've made in the MAF correction? Do I need to start over on the MAF correction?
Hope this makes sense..
i know what you mean, if i get the LTFT dialed in, and then make a few changes to the STFT the LTFT will be off again
2008 HHR SS 5-speed
HP-Tuned
Yes, if the STFT's at a cruise RPM are pulling the LTFT's around, when you compensate for them the LTFT will need a bit 'o tweak.
When you are getting very close the LTFT's should move very little over a long varying drive like highway to speedrun to stop & go.
My LTFT's still pull around .8 positive in stop & go traffic, usually -0.8 to 0 on the open road. I can't pin them down any better here.
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
Guys, I am running stock filter and airbox mod and stock everything else. I have not made any adjustments to the freq table. I made little adjustments to cells with more than 50 hits to the correction table. I noticed that the better I get my stft's, the better my ltft's have gotten. I started with some drivability issues in the less than 3k area. I would call it a small hesitation or pulsation when accelerating through the 1.5k to 3k area. Very annoying in stop and go. I went back and looked at the logs and found the stft dropping low accelerating in those areas. This would cause a drop in the actual lambda over the commanded. I am guessing this is what is causing the hesitation? I have done a lot of logs/adjustments in this area and feel I have made significant improvements. I am still getting a slight pulsation in first and second on up are very good.
2009 SS/TC
Thanks for the input Geoff
So essentially, as stated in the guide, get the LTFT as close to 0 or -0.8 by working the Frequency table. After that, work the STFT, which will affect the LTFT but as you get closer with the STFT, you may or may not have to make any changes to the freq. table and if so, it will only affect the LTFT?
Thanks for your help on this Tom.
I guess I stated it wrong above, but if your STFT's are off, it will pull your LTFT's around.
Get the LTFT's as close as possible, then work the correction table for the STFT's. That's how I do it anyway. Once the STFT's are dialed in the LTFT's will stay put.
My experience leads me to believe STFT's logged around -1.5 will keep the LTFT's around -0.8 to 0.0 on mine anyway. I prefer the LTFT's at -0.8
When I has the Hahn CAI & MAF on it, I would get the LTFT's pretty close until I cruised around 80, (~5k MAF freq) then they would go negative 3-4 until I worked out the STFT in the cells on the correction table. It was a turbulent range of the intake I had issues with.
Life is much simpler with the MAF relocated to the lower CP. HTH
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
i can't get the STFT to dial in, how long should it take? mine looks like and ocean wave while the LTFT are at 0 -.8 or so
2008 HHR SS 5-speed
HP-Tuned
The charts will look like a wave as it responds while logging. It always measures & corrects.
Use the histograms for tuning the STFT. (STFT+LTFT) vs Load & RPM
'12 Camaro T3 2SS/RS LS3 M6, SLP TVS 2300, Flex Fuel
I recently have gone back to doing it my old way and Im getting better results lately. I also tried something else that I will share
First things first:
I tune the freq table by making a histo for LTFT only vs the freq table
Then make a histo for the corr table using STFT only.
I then dial in the Freq table a time or 2 and ignore the Corr table for now. Then do paste by 1/2% on the corr table and all should be inline!
Another thing Ive been doing:
Make the entire Correction table 1's, then work the freq table and move back to the corr table like mentioned above. This has greatly minimized the dip on WOT and in between shifts using NLS the Lambda readout is a flat line for me!! Ive tried this on a few others cars now and they seem to like it as well! The car seems quite a bit more responsive on stabbing WOT
Something to try out!
yes, i will have to try that one out
2008 HHR SS 5-speed
HP-Tuned
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