so I changed out my stock intake for cold air one the diameter of the intake is 3 1/2" where I find the tables to adjust for the increase in size. because I can't seem to figure that out. when lifted off the throttle the car will continue to gas (accelerate) for a second or two the dfco kicks in. I'm guessing this is a direct result of an increase in diameter. here's the part for reference:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Originally Posted by stephenmerry101
The coyote would benefit a lot better from a jlt or pmas cold air
Not for a true street driver. That CAI actually looks like one of the most appropriately sized ones Ive ever seen for a stocker thats a street daily.
I have no experience with that specific one but the maf periods transfer function is where you dial in the new maf.
so how do I go about dialing it in because the maf is approximately 2x the distance from the engine now I don't fully understand how periods work. and don't even know the stock intake size to adjust lbs/min and maf airflow vs period. plus I'm trying to figure out how this all works
Last edited by stephenmerry101; 03-31-2021 at 10:05 AM.
If you adjust your maf period it will change the fuel trims and your log shows less than 1% LTFT learned error... You should add a few pids to the log:
Throttle Angle
Throttle Angle Error
ETC Model Vacuum
ETC Effective Area
ill do one in 5 min
here's what I have so far I tried editing it I turned off MAF acdc and it seemed to make no difference. I know it the intake because I swapped back to the old one and the issue disappeared. I don't know what exactly to edit for housing size and the distance increase (2x father from throttle body)
Your mass air meter was calibrated by some nerds more nerdy than me... I bet that sucker is right and you need to edit your predicted throttle angle. I'm new and I don't know what to do tho:
MasterTuner.jpg
It looks like you are going the wrong way with the MAF table. It being a little farther from the engine might effect transient stuff slightly, but the general fueling and steady state it shouldn't mater. Its the size and characteristics of the tube the MAF sensor is in that matter. Leave MAF ACDC enabled, and the tip in/out stock.
From the first log I would have went 2% less the entire curve, multiply by .98
From the second log I would have done 10% less the entire curve , multiply by .9
It looks like this tube is actually slightly smaller than stock MAF housing. That is probably fine and may give you better low end torque. It could also be why it has that throttle hanging open slightly for a second or two when you let off with the stock MAF curve.
Open the scanner and add mass airflow period [TIME] to your scanner. You will setup a graph with the period values from your tune file in the Row with it. You will then populate the graph with LTFT+STFT and that will be the error you need to correct the MAF table with. you will be near 0% on both LTFT and STFT in no time.
-10%.PNG
Last edited by murfie; 04-01-2021 at 01:48 AM.
considering that I had maf acdc off ill turn it back on and then multiply my .98 for now and set the log up the way you explained and see what happens then. thank you
this was better then, the problem came back a little while after coming back from work. I am going to try .90. honestly, I just changed my closed throttle thresh and throttle angel min to 3 degrees, and the problem completely disappeared. highly confused, was doing it to see if it probably had something to do with throttle or fueling purely. the last question I have is what does the negative or positive percentage mean on ltft and stft.
The fuel trims are how much fuel is being added or removed from the ratio calculation.
The error is coming from the mass of air being wrong. In your case its because you changed the tube the MAF is in.
From this .95 log I would say another -5% would put fueling back where it should be. you really should add Mass airflow period to your channel list before doing your next log. From there you know your airflow/load calculations are correct and then can look into a throttle issue if it doesnt fix it.
Last edited by murfie; 04-02-2021 at 05:47 AM.
thank you, will correct now, and the corresponding channel for MAF periods. just need a couple of hours to do so.
so the accel problem stopped for the most part I did it 2 the entire drive for a smaller amount of time but lemme know if the maf is more dialed in now I think from what I see it is but now I have to figure out where this smoke is coming from it came out my driver side vent into the car nothing on the outside. I'm not sure what that's about.
I didn't realize your spark tables were so aggressive. It is right on the borderline knocking (or cylinder pressure limit is saving it). Leave the MBT tables stock unless you are running E85, Even then 30-31* max(at higher loads) and less near the peak torque RPMs. Giving it the ability to see 35-36* on gasoline is not smart.
MAF looks better, its getting the scanner to poll the data faster and fine tuning from here. We are not seeing the full picture.
Right now its important to work on the scanner and getting it to give you what you need to see, at the rate you need to see it.
Channel polling speed.PNG
This is what it is currently gathering. As you can see SAE channels are really slow, one channel at a time.
Last edited by murfie; 04-03-2021 at 03:17 AM.
I know people search for the right channels all the time and cant find them. I'm going to add an XML you can use that will give you the basic channels you need for tuning a near stock 15+ mustang (basically anything NA). If you load this into your channel list and any come up grey you need to contact support and have them add it to your strategy.
15Mustang.Channels.xml
For comparison, this is the data it pulls out using this channel list on my own car.
Fast Channel polling speed.PNG
-Right click your channel list and select remove all channels.
-select the folder with the gear in the top left
-select open channel config
-browse to where you downloaded that XML
-Confirm none are greyed out
-take a log
Last edited by murfie; 04-03-2021 at 04:43 AM.
Thank you, I'm actually switching back to e85 after locking in the MAF I'm starting to getting get the hang of it the MAF is coming together but I do have one more question with the increase of nanoseconds is that more airflow. or the lower end like the 83 Nanos is seeing more are flow I just need to make sure.
When you figure out what percent alcohol your e85 is, here is the formula you use to get the value for your stoich AFR I told you about: <% ethanol> * 9.0078 + <% gasoline> * 14.64
Period= 1/frequency
So a lower period means a higher frequency, meaning more airflow.
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