Hey,
I'm having a few problems with tuning my low rpm ve tables.
My mods list is included in my profile, so you know what I am working with.
I used the formula to find my new injector constant for the Siemens Deka IV 80lb injectors
Stock constant x (stock lb/hr / new lb/hr) = New Constant
.17800 * (24 / 80) = 0.05340
I have followed Shifted's FAQ, "HP VE Tuning - The Easy Way" in setting up:
Open loop operation enabled (ECT vs. Startup ECT, PE AFR, PE Delay, AFR vs. ECT, IPW vs VAC)
Injector Constant (Changed from .17800 to .05340)
DFCO is disabled
Fuel pressure at the rail is 50 psi.
Ve Offset has been increased to 50% (All VE tables were scaled back down to compensate)
When I log and copy, paste add the histograms into the VCM Editor, my tune goes out of whack the more and more I try. It always shows a log that I am really lean in the 6.2% and 9.4% throttle areas. I keep paste adding the VE tables, and it just creates more peaks and valleys, which results in horrible fueling, and surging at low throttle conditions.
My histograms don't EVER seem to pick up readings in throttle positions above 18.7% or 25%
Here's a copy of my files.
What is the wideband reading in these areas?
98 S10 2.2 ln2 T3-T4 turbo.Custom made by me. 5spd. Forged pistons, H-beam rods, cometic mls. 50lb delphi's. 57mm throttle body. 3in downpipe full exhaust with cat. 15-20 psi everyday on a $200 fleabay turbo with 45,000 miles on it. (Dont believe everything you read on the net). Tuned by me with efilive.
On the stock flash, the wideband reads 13:1 at idle, and low rpm is anywhere between 12:1 and 18:1
The more I copy and paste add errors from repeated logging into my low rpm tables, the more it screws up. My idle turns into 18:1 instead of the 13:1, and low rpm drivability leans out and goes to heck.
My coastdown is still stock and resembles that when I drive. Letting off the gas in gear, the AFR goes to 13:1, but as soon as the clutch goes in, it shoots to 18:1 again. Doesn't make sense.
I did not modify the coastdown or idle tables, so why does my idle afr change when I alter ONLY my low rpm tables,
If anyone needs to see my stock logs vs. Newer ones to see what is going on with the low rpm VE tables, pm me your e-mail and I will send them to ya.
when just plain logging is your throttle position going from 0-100? if not i bet thats why your getting out of wack...
Throttle position is the % pid....NOT the SAE one that has been known to cause problems.
I found the thread about the throttle problems that PJ pointed out a while ago, and made sure that I am using the correct PID.
I can see the throttle % in the data logs. It reads from 0% all the way to 100% in relation to what I am doing.
There has to be some simple solution, just can't find it.
are you getting at least 50 hits in almost every cell?
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Post up your .config file. The issue has to be in there.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Here is the config file that I am using
CavyConfig
I just found a thread on the Hp Tuners website that offered a really good config file. It was created by "Old Skool" and is the last post in the following link.
Old Skool's Eco Config File
Should I be using his file? I downloaded it, cross referenced his low rpm histogram table with one of my logs, and loaded some data. The results seem to be COMPLETELY different.
Maybe my config file is a bit messed up. I noticed that in his low rpm tables his PID is set to Manifold Vacuum, where mine is set to the AFR error %.
I always thought that I was counting the percentage that the AFR was off, and adding that to the VE tables? Maybe I am mixed up in my thinking about how the VE table is used to calculate fuel?
Lolz, never saw this one before get rid of sens 121 < 14.5. Think about it, why is this here? All it does is exclude everything where your commanded afr is leaner than 14.5 and in no way helps you tune. I mean that hits all of open loop start up, all of PE, and some of closed loop cruise. Thats the only glaring issue I see. everything else looks fine.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
I removed the filter completely.
After re-opening the log, I still see crazy values.
Want to take a look at these two pics and compare my results to what I get when I pull up "old skool's" config file.
Is there a reason he is using the manifold vacuum pid, whereas I am using an AFR error one?
Should I be using manifold vacuum as a value instead??
My VE histogram
VE histogram with manifold as the PID
You cant use manifold as the pid for that one because the actual tune for the car does not use manifold vac for that table.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Hmm.
is there something else missing that you can see?
There has to be a reason why my histogram setup keeps throwing the tune way off. I don't understand why it tells me to add 20 or so in random cells, over and over. These peaks in the tables are just horrendous.
Do I need to include more pictures to help with a proper diagnosis?
Does your histograms look much different from mine? Maybe somethng is weird with my 'AFR error' PID
Are you using the ac pressure line for your wideband? Thats how it shows up in my computer when I pull up your config and load a random cavy log (have to load a log or else it thinks I'm trying to do a camaro.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Nope I am not.
AEM UEGO, custom PID. Reads the correct AFR.
Analog output wires from the wideband are connected to the Hp tuners box. Port 1 and 5 for the respected white and brown.
Well then theres an issue because I'm not getting your pids to come through when I load your config file. Post up what your afr error pid looks like.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Now on your histograms you choose aemafrerror and not afrerror in the upper right hand corner of the histogram setup display right?
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
You are talking about the "Plot Value"?
I have tried the configuration with both at different times. Gives the same reading.
This is weird.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Tell me about it.
Maybe there is something weird with my 'commanded AFR lo res' ?
Maybe I am forgetting to log a simple value in the table display?
What about resetting fuel trims? I know camaro and vette guys are resetting their trims before forced open loop logging, but when connected to the car, the fuel trim reset option is grayed out and doesn't allow changes.
Should it matter if I log my stft and ltft during open loop? AFR error doesn't use the values, and the trims aren't used in open loop at all, but is it a weird HP tuners bug?
Would upgrading to the new beta software clear a potential issue with this whole issue?
Really at a loss here.
stft and ltft dont do anything in open loop, they just stay 0.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Yep. I am forcing open loop so they aren't used.
Is anybody else using the AEM UEGO wideband with their setups? I am talking about the model # 30-5130.
Maybe I have something wrong with my Wideband PID.
If my Wideband PID formula is off, will it skew the AFR Error % readings as well?
AEM UEGO PID
like in the pic, I have it set to:
Volts / 0.421+7.3
The reading from the wideband and vcm scanner are both the same. (had to change the +10 to a +7.3)
Maybe something is wrong with this setup?
Do I have the 0.421 setting correct? Can't remember who told me to go from the 5 to 0.421, but maybe it's off and causing a problem internally?
Sorry I am not able to open the links. What bar setup are you running?
GMR has got nothing on this
