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If in 2500 row it says -5.2 then that means you need to reduce the 2500hz cell of your MAF table by 5.2%.
You can copy the 1000 to 5800hz section of this graph, then paste special-->multiply by % into your low MAF curve in your tune. Same for 5800hz and above once you get to that area.
Take trends that you see and apply them to the rest of the MAF curve that you don't have data for yet. For example, your last log the fuel trim values are going further negative the higher in the MAF curve you get.. so I would reduce the 4150 and up cells by 5-6%. Don't just blindly copy/paste special like most people do.
Also you need to be aware that for the first 10-15 mins after you flash a new tune the data you get will not be any good. It takes some time for things to settle down, so don't just start flashing/recording/flashing/recording back to back. Drive for 10-15 mins BEFORE you start logging data that you want to actually use for corrections.
If in 2500 row it says -5.2 then that means you need to reduce the 2500hz cell of your MAF table by 5.2%.
You can copy the 1000 to 5800hz section of this graph, then paste special-->multiply by % into your low MAF curve in your tune. Same for 5800hz and above once you get to that area.
Take trends that you see and apply them to the rest of the MAF curve that you don't have data for yet. For example, your last log the fuel trim values are going further negative the higher in the MAF curve you get.. so I would reduce the 4150 and up cells by 5-6%. Don't just blindly copy/paste special like most people do.
Also you need to be aware that for the first 10-15 mins after you flash a new tune the data you get will not be any good. It takes some time for things to settle down, so don't just start flashing/recording/flashing/recording back to back. Drive for 10-15 mins BEFORE you start logging data that you want to actually use for corrections.
This is great info. Do I want to turn my Long term fuel trims off when doing this? I was concerned that if my maf was so far off that my long term fuel trims might make a new base line for 0 percent. If this was the case would it show me under the LTFT chart that it was or would i not be able to tell because it set oa new base 0 line in the computer?
Also if i need to turn off my ltft while tuning the maf, where do i go for that in the editor?
Post current log/tune/layout and I'll give you some basics.
That is a very generous and exciting offer. I will update my log tonight with the maf and fuel trim changes. Then I will post the tune and log and layout.
Post current log/tune/layout and I'll give you some basics.
Hi I setup my MAF ERR Graph and have it using the wideband. I noticed there error percent is really hight at around 1000 rpm's
I will post a my next log I take today so you can take a look at what i am talking about, but is there anyway that you can explain what i am suppose to do with this data, Do I change the maf tables with it the same way i did it with the fuel trims? The fuel trim data doesn't show theses errors so i didn't want to just change them without asking the sequence.
If it's showing high error when using the WB at 1,000 RPM's then something is setup wrong. It should be close to zero there as it's in closed loop so fuel trims are already correcting for any fueling error.
Hi I setup my MAF ERR Graph and have it using the wideband. I noticed there error percent is really hight at around 1000 rpm's
I will post a my next log I take today so you can take a look at what i am talking about, but is there anyway that you can explain what i am suppose to do with this data, Do I change the maf tables with it the same way i did it with the fuel trims? The fuel trim data doesn't show theses errors so i didn't want to just change them without asking the sequence.
If you're running a closed loop tune you only really need to worry about wideband data that you see when the car exits closed loop (enters PE). Look at the cells above where you have fuel trim data in your other maf graph. Try setting up a filter so that you only see data when you're over 50% throttle.
If you're running a closed loop tune you only really need to worry about wideband data that you see when the car exits closed loop (enters PE). Look at the cells above where you have fuel trim data in your other maf graph. Try setting up a filter so that you only see data when you're over 50% throttle.
So I any tips on how to make that filter you mentioned?
Also are you saying I can go out and open throttle and the just use my wideband err chart to make changes to the maf tables the same way i would from the fuel trim logs?
If so this should be pretty easy. Also do I have to worry about breaking my motor in WOT ?
Yes there is a parameter in HPT that compares wideband AFR vs. Commanded AFR and gives a % error. So if it's commanding 12.5:1 and actual is 13:1 then it'd show ~4%. Then it's the same as the fuel trim graph you were working with earlier. Increase that cell of MAF table 4%.
As long as commanded AFR is ~14.7 then you use the fuel trim one
As soon as commanded AFR changes away from that then you have to use the wideband one
You can setup filters to make it do it automatically.
If you'll post a log/layout then I'll show you how to do it.
Yes there is a parameter in HPT that compares wideband AFR vs. Commanded AFR and gives a % error. So if it's commanding 12.5:1 and actual is 13:1 then it'd show ~4%. Then it's the same as the fuel trim graph you were working with earlier. Increase that cell of MAF table 4%.
As long as commanded AFR is ~14.7 then you use the fuel trim one
As soon as commanded AFR changes away from that then you have to use the wideband one
You can setup filters to make it do it automatically.
If you'll post a log/layout then I'll show you how to do it.
Thank you.
I'll go create a log right now and upload it.
Yes there is a parameter in HPT that compares wideband AFR vs. Commanded AFR and gives a % error. So if it's commanding 12.5:1 and actual is 13:1 then it'd show ~4%. Then it's the same as the fuel trim graph you were working with earlier. Increase that cell of MAF table 4%.
As long as commanded AFR is ~14.7 then you use the fuel trim one
As soon as commanded AFR changes away from that then you have to use the wideband one
You can setup filters to make it do it automatically.
If you'll post a log/layout then I'll show you how to do it.
Here is my log and layout,
My AFR Er at 1000 rpm went away after I added a clamp to the intake hose.
I'm really interested to see how this is done.
I added this filter to my wideband MAF ERR graph
([50090.156] > 50) AND ([50090.156.avg(500)] > 50) AND ([50090.156.avg(-500)] > 50)
Try this layout. I made your charts a bit more useful and added some graphs for AFR error. Also added one that shows commanded AFR and one that shows the average WB reading for the heck of it.
The AFR error ones willl only show data if commanded AFR is richer than 14.6 (which never happened in this last log so that is why it's showing up blank).
There are other ways to do it but that seemed like the simplest for the time being. Also fixed the spark timing table so it will match up with your tune better
You aren't logging knock retard so that is why that one is showing up blank. Add knock retard to your channels list and it should start working.
Try this layout. I made your charts a bit more useful and added some graphs for AFR error. Also added one that shows commanded AFR and one that shows the average WB reading for the heck of it.
The AFR error ones willl only show data if commanded AFR is richer than 14.6 (which never happened in this last log so that is why it's showing up blank).
There are other ways to do it but that seemed like the simplest for the time being. Also fixed the spark timing table so it will match up with your tune better
You aren't logging knock retard so that is why that one is showing up blank. Add knock retard to your channels list and it should start working.
Thank You,
The filter makes sense (AFR cmd greater or less than 14.6)
After this is all tuned in would it be beneficial to do a filter that monitors 70% or higher throttle?
Also you have a guide for VE vs Fuel Trims. Would this work for PE tuning if I changed the parameter from fuel trims to my wideband?
And if so should I use the same afr less than filter you showed me or should I use a percentage of throttle? or both
Also If I have both fuel trim data for under PE and AFR data for PE for the same tables what do I do? Do I put in the fuel trim data first then drive a new log and when that is at zero then start PE table MAF changes?
Thank you
You can play with the filters and see what works best for you. I don't have a great way of doing it--some guys use formulas that filter out a certain amount of time before/after going into PE and all kinds of other stuff but I've found a little common sense and looking at both the graphs and charts to see what is going on can help as much as anything.
I've added a fuel trim error vs. VE table and a wideband AFR error vs. VE table in the attached layout for tuning VE.
Before messing with the MAF table you really should set it to MAF only mode.
Airflow-->dynamic, set disable to 200 RPM's and re-enable to 100 RPM's
For turning VE, you'll want to disable the MAF by going to engine diag-->airflow. Set the MAF fail freq high to something really low like 1hz
You can play with the filters and see what works best for you. I don't have a great way of doing it--some guys use formulas that filter out a certain amount of time before/after going into PE and all kinds of other stuff but I've found a little common sense and looking at both the graphs and charts to see what is going on can help as much as anything.
I've added a fuel trim error vs. VE table and a wideband AFR error vs. VE table in the attached layout for tuning VE.
Before messing with the MAF table you really should set it to MAF only mode.
Airflow-->dynamic, set disable to 200 RPM's and re-enable to 100 RPM's
For turning VE, you'll want to disable the MAF by going to engine diag-->airflow. Set the MAF fail freq high to something really low like 1hz
Great Info. So are you saying its a choice on weather to use the AFR err maf data or the fuel trim maf data because they both are correct?
I'm saying they are both correct for different circumstances. In closed loop use fuel trims. In open loop (I.e. WOT) use the AFR error ones.
And.. As stated earlier, apply common sense.. Look at the chart vs. Time and you can get a bit better visual idea of what's going on.. I put the commanded AFR and actual AFR right on top of each other so you can see if it's lean or rich. It will always bounce around some.
I'll look at the log in a bit
Post the tune also--I think there are some PE settings that could use adjusting but can't be sure without seeing it
Looking at the charts will also help you see what areas are actually lean or rich and what areas are just the WB being slow. If you look at 13:32:945 you'll see what I mean.. it looks really lean right there but I bet it's just the WB being slow to react
07-08-2016, 09:50 AM
(AFR cmd greater or less than 14.6)