MAF Calibration 101

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vortk355
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Joined: August 1st, 2018, 5:55 pm

Re: MAF Calibration 101

Post by vortk355 »

Mazdaspeed 6
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Ugnius @ VersaTune
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Re: MAF Calibration 101

Post by Ugnius @ VersaTune »

MAF preset.png
MAF preset.png (228.87 KiB) Viewed 21991 times
vortk355
Posts: 3
Joined: August 1st, 2018, 5:55 pm

Re: MAF Calibration 101

Post by vortk355 »

Right there in front of me lol.
Thank you!
bambam787
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Joined: February 1st, 2021, 1:10 pm

Re: MAF Calibration 101

Post by bambam787 »

hello there, i have a good knowledge about tunning and numbers but completly new to versatuner. the only part i dont get about the MAF calibration
is when i have the numbers ready from the logs and already input the numbers into the maf worksheet ....so i open up the map im working on go to calibration then MAF ..now what do i do ?????? cant seem to be able to delete the whole thing or able to use correctly the multiplier ....really have no idea lol and im ussualy pretty good about this things ...i can even straight copy and paste ...i dont even see the smoothing thing that ive seen everyone talks about ....anyone help ? if you can post screenshots or a mini video would be gladly appreciate thank you
Last edited by bambam787 on February 3rd, 2021, 7:11 am, edited 1 time in total.
mituc
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Re: MAF Calibration 101

Post by mituc »

If you need to apply a multiplier just select the whole vector (CTRL+A) and apply the multiplier you want. You can do that for the whole calibration or only for a section of it.
Deleting the whole thing will not work, you have to have something in there. However you can paste new values over.
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amiara
Posts: 18
Joined: March 20th, 2022, 11:22 pm

Re: MAF Calibration 101

Post by amiara »

Thanks for the instruction.

I cleaned the MAF sensor with CRC cleaner and reset the ECU. Actual AFR readings show random peaks in lambda up to 2.0!! i even had some random peaks at 2.0 before cleaning and reseting the ECU. How this is possible? there is no LEAN code error in the diag.


Could you please have a look at the log?
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Mass airflow sensor calibration - 2022-04-18 00.42.48.csv
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wcs
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Joined: May 12th, 2021, 12:46 am

Re: MAF Calibration 101

Post by wcs »

The 2.0 lambda (or if you're logging in AFR you'll see 20 afr) occurs when you take your foot off the gas.
There is a fuel cut during the decel condition. (this is normal on the RX8)

Go out and do a simple log cycling thru "on" the gas then completely "off" the gas, you'll see this every time on a stock tune.
You should see 2 lambda or 20 afr and similar readings for the STFT.

At a glance your Long Term fuel trim looks especially jacked.
LTFT is +20 in many of the cells - IMO even after doing a reset on the ECU it seems pretty weird to see a LTFT already at +20 though this may drop as you get more mileage on the ecu after the reset.
That said I would be looking for a vacuum leak, a common issue.
However the voltage being reported across the maf sensor looks ok ..soooooo

Do you have a modified intake?

Also I recommend when you are doing logs, try to log for a single condition.
For example don't mix your Idle Log in with your Wide Open Throttle log (WOT) or the Cruise Log (3000 rpm Cruise in 4gear log for example).
At least for the purposes of posting.
(There are software packages that can parse through a drive log that covers as many conditions as you can put the ecu through. I use MegaLogView HD for that)
HarryPotter69
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Joined: February 20th, 2024, 8:42 am

Re: MAF Calibration 101

Post by HarryPotter69 »

Sure, it seems like you're talking about monitoring the air-fuel ratio and fuel trims on a Mazda RX8. During deceleration, lambda readings of 2.0 or 20 AFR are normal due to fuel cut-off. A high Long Term Fuel Trim of +20 could indicate a vacuum leak. Checking the intake system for leaks is a good idea, especially if there are modifications. Logging data for single conditions is recommended for easier analysis. MegaLogView HD is a useful tool for parsing through drive logs efficiently.
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