• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

sort out fuel trims

04lss

04lss

New member
Hi all,

Right now im running e85 on my stock injectors with a 3.5 pulley.

I have been trying to sort out the fuel trims, but it just doesnt seem to be working.

I unplugged my MAF and logged as suggested in the tunning for dummies how to.

I went into Airflow and primary VE and adjusted each of the values the log gave me. When the fuel trim was 5% i added 5% to value in the table. When the trim was negative, i subtracted 5%.

I went and logged today with the MAF plugged in and the LTFT seems like its even higher. Non of the values moved towards 0. I even parked, let the car idle and learn the idle LTFT values, went into the tune and added twice that amount to the table for those values, restarted and re logged and there was virtually no change. What am i doing wrong?

I changed my fuel filter, it was pretty stopped up about 2 tanks ago. Should i try that again? I did max my injectors on this log which has never happened before. Maybe the new filter is clogged? or maybe all of the gas is out of the car?

Some other details, the injector gain is set to 1.33

here is a link to the log file and tune, my WOT pull is pretty much at the end.

Update your browser to use Google Drive - Google Drive Help
 


first things first: plug that maf back in and don't bother tuning your ve. the ve is only a backup and doesn't have any bearing on how the car will run unless the maf fails.

edit: second: are you logging throttle percentage? you also need to be logging your O2 sensor. also, on the scan I downloaded, your maf table only shows one value, are you logging it right?
 
Last edited:
SgtMarshal said:
first things first: plug that maf back in and don't bother tuning your ve. the ve is only a backup and doesn't have any bearing on how the car will run unless the maf fails.

edit: second: are you logging throttle percentage? you also need to be logging your O2 sensor. also, on the scan I downloaded, your maf table only shows one value, are you logging it right?
Click to expand...

I used whatever the stock setup was for the VCM logger.

I will try and add the o2 sensor and the MAF table (i dont see one in the graph). I did see values change in the gauge area.

I have no idea if I am doing this right. Where do i adjust fuel then if not VE? Which table should I be working with?
 
you add and take fuel away depending on your O2 sensor to your maf table. you need to follow the instructions in the "starting hp tuners" thread to set up your maf table.
 
scroll down to where it says this and follow the directions

Now we are going to make some custom histograms to log what we want and make is easy to use. Starting with plotting LTFT's on to the maf table.
To do this you will have to go into the primary table. The primary table shows what sensor are being logged by the scanner.
 
ill set lower maf if need be with ltft. stock maf you dont always need to touch down low. but up top you may have to. ill do a scan and watch maf hurtz and what the wb says. if you pause the scan and use the arrow keys to move ahead its like a second a click of the button,

you need to set your pe afr to 1.200 and see where you land on the commanded, small amounts from there up or down with dial it in to where you want it, mid 11's.

set pe enable to like 30% hot. so now you know when you see 30% throttle you should be in pe mode commanding the lower afr. now watch the wb as the scan goes, you want the wb to match the commanded, so if its not matching you look at maf hurtz and the wb and raise to add fuel, lower to remove fuel to those cells.


i dialed my n* maf using this part of the scanner only pretty much.
attachment.php
 

Attachments

  • 237.jpg
    237.jpg
    180.2 KB · Views: 70


Scottydoggs said:
ill set lower maf if need be with ltft. stock maf you dont always need to touch down low. but up top you may have to. ill do a scan and watch maf hurtz and what the wb says. if you pause the scan and use the arrow keys to move ahead its like a second a click of the button,

you need to set your pe afr to 1.200 and see where you land on the commanded, small amounts from there up or down with dial it in to where you want it, mid 11's.

set pe enable to like 30% hot. so now you know when you see 30% throttle you should be in pe mode commanding the lower afr. now watch the wb as the scan goes, you want the wb to match the commanded, so if its not matching you look at maf hurtz and the wb and raise to add fuel, lower to remove fuel to those cells.


i dialed my n* maf using this part of the scanner only pretty much.
attachment.php
Click to expand...

I don't have a wide band o2 yet. I'm just trying to get my fuel trims down to + or - 4
 
Guys, im sorry if i'm dense but what table should i be adjusting to increase or decrease fueling? Where do i Find the "MAF" table?
 
I think ive gotten the scan right ... Should be obvious which log file it is. I just ran the car for a few minutes to check.

If someone wouldnt mind taking a look: Update your browser to use Google Drive - Google Drive Help

On another note:

I will be chaning my injectors to the Deka 80#. How do i go about doing that? i recall reading that i need KPA ... zzp says the following Static Flow Rate @ 43.5PSI ( 300kPa ) w/Gas: 80 lb/hr = 630 cc/min = 850 cc/min Is that useful at all?
 
I found the Flow vs KPA table, should i just enter 80? looks like the values change a bit based on pressure, should i just divide 80/33 and multiply the figures in the table by that?
 


I have read that the idle with the 80s can be difficult on pump gas because they are so large, anyone else hear of this?
 
They may idle a bit rich, but you should still be able to get them close. My buddy ran 95' and was able to idle around 14.
 
I am installing all of my mods tomorrow. I have read that you can run a lot richer with e85 without loosing power, to help with cooling the charge etc. what table would i change to tell the car to run a bit richer? I would like to start out rich, and inch it back towards stock just for safety.
 
you dont want to be richer. set pe to 11.5, watch the wb to make sure its reading the same, if its not you add to the maf.
 


What you read is correct. A richer afr with e85 doesnt decrease power the way it does with regular fuel.

The easiest way to add fuel is with the base PE table. You can richen it up a full point, then slowly dial it back til you get to the afr you want.
 
rickisrad said:
How imperative is it to log trims without disabling the Power Enrich? Asking for a friend.
Click to expand...

What do you even mean? I mean, can you clarify what you are trying to do? If you have no PE enabled, definitely dont take it over 7000ish hz. Are you trying to tune with narrowband?
 
You must log in or register to reply here.
Back
Top