Ve tuning guide
#11
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Originally Posted by 02sierraz71_5.3
yes keep it at 0
the maf shouldnt be unplugged has the iat sensor in it, the se light will effect nothing on or off same with the code for the maf
the maf shouldnt be unplugged has the iat sensor in it, the se light will effect nothing on or off same with the code for the maf
Since the MAF has the IAT sensor in it, I wonder if having it unplugged screwed up my LTFT readings when I was adjusting them yesterday???
Also, I noticed my check engine light was on today. But I never re-enabled the SES light from yesterday. Are these two the same or is the SES light something different?
I'm going to check the codes today after work.
#12
Originally Posted by Zick
Since the MAF has the IAT sensor in it, I wonder if having it unplugged screwed up my LTFT readings when I was adjusting them yesterday???
Also, I noticed my check engine light was on today. But I never re-enabled the SES light from yesterday. Are these two the same or is the SES light something different?
I'm going to check the codes today after work.
Also, I noticed my check engine light was on today. But I never re-enabled the SES light from yesterday. Are these two the same or is the SES light something different?
I'm going to check the codes today after work.
#13
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The codes were P0102, P0103. Having to do with the MAF.
Also ran another scan today after plugging the MAF back in. My LTFTs where all almost around 8-13.
Adjusted them back down, but I'm not sure if I'm even doing this right. I'm probably just gonna start from scratch again.
Also ran another scan today after plugging the MAF back in. My LTFTs where all almost around 8-13.
Adjusted them back down, but I'm not sure if I'm even doing this right. I'm probably just gonna start from scratch again.
#14
Originally Posted by Zick
The codes were P0102, P0103. Having to do with the MAF.
Also ran another scan today after plugging the MAF back in. My LTFTs where all almost around 8-13.
Adjusted them back down, but I'm not sure if I'm even doing this right. I'm probably just gonna start from scratch again.
Also ran another scan today after plugging the MAF back in. My LTFTs where all almost around 8-13.
Adjusted them back down, but I'm not sure if I'm even doing this right. I'm probably just gonna start from scratch again.
Ive wanted to drive this thing off a cliff so many times just keep tuning the lt's it will be worth it in the end. dont forget to reset trims after every ve adjust
#16
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i pretty sure the IAT sensor has to be operable in order to tune via SD. i would put the MAF back in place and just set the MAF Freq Fail to 0. this will still get you in SD and still have the IAT in there.
#17
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I like the last paragraph
because its something thats not talked about alot
the end of the ve graph
alot of the files I have seen seems to drop after the 3600
column
mine done it too
this is about where I would spin it to when tuning the ve table part throttle
and looking at it further I noticed positive numbers in the 28 32 36 columns
Id say an avg of 5-6%
I also noticed I was having to command an extremely rich afr in the PE table and my O2s were still showing lean
sometimes Id even notice mine hitting +2 or +3
when in PE
and still be lean
so I set it to command 12.5 and added 5 to the VE table
from 2800 up and hand tapered/smoothed it off on a line I assumed it was trying to follow(if that makes any sense? ...2d line)
It brung my O2 readings between 870-890 on the first try
my take on it is
the fuel trims add fuel based on your 02 readings at part throttle to correct for an inaccurate VE table
and other conditions
when at wot and in PE mode it still calculates thru the ve table and thats why you see so many commanding off the wall afr's thru the PE and wild IFR tables
dont lie to your PCM
all because they dont hit those cells when tuning the VE table
but having said that who wants to spin one up to 6K+ at 14.7 ?
but you can always guess and tweak a little at a time on the VE table until you get it right or close based on your o2 or afr readings
that or command 13:1 and run it on up into those WOT cells
Ive been told that the VE table is nothing but the small **** for the tuning and it should be left alone
I have to disagree
its the whole backbone of your fuel
from 15 to 105kpa and 400 to 8000 rpm
based on percent fuel added
I may be wrong
but thats the way it works for me
oh and chris...
dont drive it off a cliff
dont blow it up either
lol
because its something thats not talked about alot
the end of the ve graph
alot of the files I have seen seems to drop after the 3600
column
mine done it too
this is about where I would spin it to when tuning the ve table part throttle
and looking at it further I noticed positive numbers in the 28 32 36 columns
Id say an avg of 5-6%
I also noticed I was having to command an extremely rich afr in the PE table and my O2s were still showing lean
sometimes Id even notice mine hitting +2 or +3
when in PE
and still be lean
so I set it to command 12.5 and added 5 to the VE table
from 2800 up and hand tapered/smoothed it off on a line I assumed it was trying to follow(if that makes any sense? ...2d line)
It brung my O2 readings between 870-890 on the first try
my take on it is
the fuel trims add fuel based on your 02 readings at part throttle to correct for an inaccurate VE table
and other conditions
when at wot and in PE mode it still calculates thru the ve table and thats why you see so many commanding off the wall afr's thru the PE and wild IFR tables
dont lie to your PCM
all because they dont hit those cells when tuning the VE table
but having said that who wants to spin one up to 6K+ at 14.7 ?
but you can always guess and tweak a little at a time on the VE table until you get it right or close based on your o2 or afr readings
that or command 13:1 and run it on up into those WOT cells
Ive been told that the VE table is nothing but the small **** for the tuning and it should be left alone
I have to disagree
its the whole backbone of your fuel
from 15 to 105kpa and 400 to 8000 rpm
based on percent fuel added
I may be wrong
but thats the way it works for me
oh and chris...
dont drive it off a cliff
dont blow it up either
lol
#18
Originally Posted by gamedawgx53
I like the last paragraph
because its something thats not talked about alot
the end of the ve graph
alot of the files I have seen seems to drop after the 3600
column
mine done it too
this is about where I would spin it to when tuning the ve table part throttle
and looking at it further I noticed positive numbers in the 28 32 36 columns
Id say an avg of 5-6%
I also noticed I was having to command an extremely rich afr in the PE table and my O2s were still showing lean
sometimes Id even notice mine hitting +2 or +3
when in PE
and still be lean
so I set it to command 12.5 and added 5 to the VE table
from 2800 up and hand tapered/smoothed it off on a line I assumed it was trying to follow(if that makes any sense? ...2d line)
It brung my O2 readings between 870-890 on the first try
my take on it is
the fuel trims add fuel based on your 02 readings at part throttle to correct for an inaccurate VE table
and other conditions
when at wot and in PE mode it still calculates thru the ve table and thats why you see so many commanding off the wall afr's thru the PE and wild IFR tables
dont lie to your PCM
all because they dont hit those cells when tuning the VE table
but having said that who wants to spin one up to 6K+ at 14.7 ?
but you can always guess and tweak a little at a time on the VE table until you get it right or close based on your o2 or afr readings
that or command 13:1 and run it on up into those WOT cells
Ive been told that the VE table is nothing but the small **** for the tuning and it should be left alone
I have to disagree
its the whole backbone of your fuel
from 15 to 105kpa and 400 to 8000 rpm
based on percent fuel added
I may be wrong
but thats the way it works for me
oh and chris...
dont drive it off a cliff
dont blow it up either
lol
because its something thats not talked about alot
the end of the ve graph
alot of the files I have seen seems to drop after the 3600
column
mine done it too
this is about where I would spin it to when tuning the ve table part throttle
and looking at it further I noticed positive numbers in the 28 32 36 columns
Id say an avg of 5-6%
I also noticed I was having to command an extremely rich afr in the PE table and my O2s were still showing lean
sometimes Id even notice mine hitting +2 or +3
when in PE
and still be lean
so I set it to command 12.5 and added 5 to the VE table
from 2800 up and hand tapered/smoothed it off on a line I assumed it was trying to follow(if that makes any sense? ...2d line)
It brung my O2 readings between 870-890 on the first try
my take on it is
the fuel trims add fuel based on your 02 readings at part throttle to correct for an inaccurate VE table
and other conditions
when at wot and in PE mode it still calculates thru the ve table and thats why you see so many commanding off the wall afr's thru the PE and wild IFR tables
dont lie to your PCM
all because they dont hit those cells when tuning the VE table
but having said that who wants to spin one up to 6K+ at 14.7 ?
but you can always guess and tweak a little at a time on the VE table until you get it right or close based on your o2 or afr readings
that or command 13:1 and run it on up into those WOT cells
Ive been told that the VE table is nothing but the small **** for the tuning and it should be left alone
I have to disagree
its the whole backbone of your fuel
from 15 to 105kpa and 400 to 8000 rpm
based on percent fuel added
I may be wrong
but thats the way it works for me
oh and chris...
dont drive it off a cliff
dont blow it up either
lol
Im glad someone saw that its taken me a long time and alot of frustration to realize that if you can command 14.7 throughout the whole ve then the pe math will be inline, I know its simple but no one thinks that way. I tuned my ve uptop according to this principle set the the pe table to 1.112 and leave it if you are leaning out up top its because of the ve not commanding 14.7 but a leaner value. This can be covered up by the maf but its spuradic I want my fuel to be consistent always god damnit and GM sure didnt make it easy
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Its taken a while but i think we got it
all the conversations and frustrations we had finally paid off
the biggest problem I had was understanding what each table did and why
but after I did understand
it just all come together at once
good writeup buddy
all the conversations and frustrations we had finally paid off
the biggest problem I had was understanding what each table did and why
but after I did understand
it just all come together at once
good writeup buddy
#20
Would someone please post their current nicely tuned VE table for a stock 5.3? I know it will need some tweaking after that, but it would at least give a bunch of us a baseline and save tons of time...?