Lnf trims

Stretch2126

Well-Known Member
I’ve been trying to narrow down knock and what I think is a lean spot. LTFT sits around 10-14% while afr is good(probably from correction) and stft is negative cruising but will climb positive into a long wot pull. I’m stuck on if I need to recalibrate the MAF since I have a short open exhaust and a different air filter or find something else. I’ve already unplugged the battery to reset trims once, but the Ltft just climbed up again. Everything in boost seems good after command lambda comes in, but in vacuum it sometimes has KR and the Ltft is showing lean.
I have new spark plugs that are one step colder to help fight knock since I’m running 22-24 psi on a ko4. Also I have new coil packs. Help is greatly appreciated since I’m brand new to tuning
 

Stretch2126

Well-Known Member
Also I forgot to mention the log always says “cl-fault” even though the afr is technically where it needs to be.
 

JBINTX

Goblin Guru
If you are interested, I can share my tune to use or just for reference. It originally was done on a dyno at ZZP. K04 turbo and boost set to 24 or 26 (I forgot which). I have 3 bar map sensors. Rest is stock or standard DF supplied.
pm me if so interested.
 

Stretch2126

Well-Known Member
If you are interested, I can share my tune to use or just for reference. It originally was done on a dyno at ZZP. K04 turbo and boost set to 24 or 26 (I forgot which). I have 3 bar map sensors. Rest is stock or standard DF supplied.
pm me if so interested.
I appreciate it. I have the same thing I just have a 10inch tube for an exhaust and an AFE air filter that flows much more. Also I’m in Florida with a much lower altitude so I believe it’s underestimating the air going in.
 

Gtstorey

Goblin Guru
Yes you need to tune and also find out why you are getting the closed loop fault.

Do you have HPTuners? If so post the tune and a log.

LTFT is a single number on the LNF applied over all running conditions. So positive LTFT with positive STFT means it's still trying to run lean up top and is fighting to add fuel to correct it. Add in the stock PE being on the lean side for the added boost and it sounds like it can't get enough fuel.

And PE is added based upon some combination of throttle and pedal %, so it's possible to build boost without the full benefit of the enrichment.
 

Stretch2126

Well-Known Member
I do have HPTuners. The PE table is not stock, I added fuel to be safe a while back. 100% throttle being .81 lambda. I am just unsure if need to recalibrate the MAF due to the filter and exhaust or if I am going in the wrong direction. Also I run a small water/meth injection kit sometimes to clean the intake and pistons every now and then but I do not plan to rely on it. I didn't use it in this run.
 

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Gtstorey

Goblin Guru
I think all LNF would benefit from maf tuning. And the more you move away from stock, the more important it is. I'll look over the tune and log when I get a chance.

The PE is just more than setting it for 100% throttle. You need to compare it to how much boost it's building. Depending on a lot of other tables, it's possible to be building boost well before the "throttle" is 100%.
 

Stretch2126

Well-Known Member
I think all LNF would benefit from maf tuning. And the more you move away from stock, the more important it is. I'll look over the tune and log when I get a chance.

The PE is just more than setting it for 100% throttle. You need to compare it to how much boost it's building. Depending on a lot of other tables, it's possible to be building boost well before the "throttle" is 100%.
Thanks I really appreciate the help.
 

Stretch2126

Well-Known Member
I can’t seem to figure out how to make a table to save my life. I tried to make it MAF vs LTFT&STFT, but copy/paste doesn’t seem to work with the calibration table because the graph is backwards or something. I reset the tune back to normal since it ran like junk with the correction table set to 1. Also it didn’t record LTFT at all during the run but I’m assuming it is because the evap is disabled and unplugged.
 

Gtstorey

Goblin Guru
You’ll have to post some screenshots of your table or all of your configuration files for someone to help figure out what is going on.

it will probably be this weekend before I have a chance to review any hpt files.

I have always tuned and ran mine with stft only.
 

Stretch2126

Well-Known Member
You’ll have to post some screenshots of your table or all of your configuration files for someone to help figure out what is going on.

it will probably be this weekend before I have a chance to review any hpt files.

I have always tuned and ran mine with stft only.
I’ll post the new run file in a minute. It had the maf correction all at 1. Also I just ordered a new O2 sensor because I just realized that the scanner has shown 0mv the entire time. I don’t understand how the afr/ lambda is just calculated on screen then if it shows 1 lambda but is still lean.
 

Stretch2126

Well-Known Member
Make sure you are looking at the correct o2 sensor.
I just started the car to take a look. B1s1 normal and sae are 0. It says CL normal for once and Long term has been stuck at 0 while short is within -3 to 7% depending on rpm.
I’m so confused lol.
 

Stretch2126

Well-Known Member
No I don’t. It’s on (MIL on x cycles). I think it’s locked on. I just did another run. Closed loop normal until I started actually moving. All the evap is disabled and I plugged the solenoid. The Ltft did go up to 4.7 quickly. O2 stayed at 0 so I’m assuming it’s gone.
 

Gtstorey

Goblin Guru
Are you monitoring “WB EQ RATIO BANK 1 and how does that compare to “EQUIVALENCE RATIO COMMANDED -BANK 1”? I haven’t been monitoring o2 voltage since it does seem to be as important with a wideband sensor.
 

Stretch2126

Well-Known Member
Are you monitoring “WB EQ RATIO BANK 1 and how does that compare to “EQUIVALENCE RATIO COMMANDED -BANK 1”? I haven’t been monitoring o2 voltage since it does seem to be as important with a wideband sensor.
Yes I am. They are both 1 at idle and eq bank 1 shows variance like it’s really reading. It follows close to the command.
 

Stretch2126

Well-Known Member
Small update. I figured out how to make the table correctly. Something is definitely wrong since the maf vs trim chart shows -80 to -90 percent. And I know I’m probably on the lean side so I’m assuming that’s from the o2 possibly being dead?
 

Stretch2126

Well-Known Member
I have the mvpi2 so the laptop rides with me. Run 5 is with the MAF correction all at 1. Run 6 was back to what I had on my original tune.
 

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