I think I read all the guides and it still does not seem to work for me. Every time LTFT are high so i add to the VE and then scan again and they dont change or get higher. I dont know what im doing wrong. pls help!

here is my first LT's


and after adding to the VE



why are they getting worse?

 

Are you resetting your fuel trims before every logging session?
And you sure that your MAF sensor is disabled? (Logging a P0102, P0103?)

(Also LTFT's take a long time to settle in. I prefer disabling the Long Term Trims and just logging STFT's and tuning with them.)

 

I tried to do what the VE write up said and my STFT went way high like in the 20's and 30's so i didnt drive around much cause i didnt want to wreck anything. so i tried to do it they why a differant write up said to( the LTFT first) it seemed to get the STFT in line but messed up the LTFT. i have been reseting trim. but is ther a sertian why to reset them like does the engine need to bo on but not running? i did it when it was running.

I have a couple more Q's to. like after i SD tune do i want ot leave it in SD and just make differant tunes for a couple differant Temps? or should i reenable the maf? and I plan on getting a wideband in the near futare am i wasting time tuning the the VE or would i need to do this anywhy?

Any help is welcome

 

Nah i wouldnt say you are wasting your time tuning with the narrowbands, granted i bought a wideband my self and needed new pants because of the difference it made. But its still worth taking the time, especially when it comes to learning how to tune.

Personally, i left my truck in OpenLoop SD for a few months and it ran just fine, i gutted my MAF anyway so theres no turning back now lol. As for needing new tunes, thats a myth, as long as you run ClosedLoop SD you're LTFT's will adjust to the small changes needed with the weather.


As for resetting the fuel trims, i'm assuming you are using HPTuners due to the screenshot, just open the VCM Controls page -> Fuel & Spark: and just click on 'Reset Fuel Trims' right before you start your logging session.

The first few times i started tuning i made a few errors myself usually just oversight of some little detail. But keep asking those questions!

 

If you disabled your ltft's and reset lt trims and your stft's where around 20-30 that means you should add that much. The numbers themselves are not imperical and therefore can be different on every engine especially with different mods. If it wants fuel IT WANTS FUEL, just because you think the numbers dont look right doesnt mean they are wrong.
Go back retune the trims and this time ignore what the actuall numbers are completely if it is adding 20 than add 20.

Im also assuming that you have the average button depressed in the histogram and not the max button.
THIS IS VERY IMPORTANT PUSH THE A

 

well my main question was, my first stft were only like 10-15 then i added that to the Ve and then they were like 20-30 so thats were i stopped. and in the ve tthats in % right should they be over 100 lots were around 90 just wondering if that was high

 

Is the average button depressed?
Is the maf fail set to 0?
If it is I would start with a stock 5.3 ve table and go from there, you can get one from horist's website.

I had a similar situation where my ve was over 100 on an NA 5.3 I just started over.

 

yes A is pressed, and maf is 0, i saved the stock ve, well i think its stock sence i bought the truck used but the truck was bone stock when i bought it so im guessing stock. Maybe i have some slow o2's i replaced one when i put the headers on. The other has im guessing 130k on it im going to try again tonight im just afraid that its going to go way lean, but i guess that would give me a reason to go out and buy that 6L

I was looking at my Ve's again and even the cells i didnt touch went lean hmm i must not be reseting my trims right or something

I'll start from scratch again tonight and hope for results

 

get a scrap HPT file and 0 out every cell in the ve table



copy your LTFTS (average like chris said) then paste- special- add into this 0'd out table

then copy your average STFTs then paste -special- add right over top of what you done before
multiply whole table by .75 to avoid overshoot

now copy that and paste -special -add to your existing VE table
reset fuel trims and go for a drive

for example if one particular cell is showing +10 stft and +20ltft that = 30 X .75 = 22.5
add that to your VE table
reset fuel trims

sounds like its really lean and wanting alot of fuel
once you get it close you can cut those LTFTs off and tweak it to its fullest

this thread should be titled "how to tune a really f'd up VE table"


as far as the resetting fuel trims
I do both with key on and running
Ive never heard an answer on this either