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**Gregski** · 02-08-2020, 03:24 PM

MAF Scaling - Calibration

You can calibrate the MAF in two ways, using either the stock narrow band oxygen sensors or using an aftermarket wideband oxygen sensor ie AFR gauge.

Option 1. Factory Narrowband Oxygen Sensor Method

To make things even more complicated, in this method you have three further choices:
Tune using only the Long Term Fuel Trims

Tune only using the Short Term Fuel Trims

Tune using both the Long and Short Term Fuel Trims simultaneously

PROS for all three choices above: you already own the narrow band oxygen sensors, you also have two of them, one in each exhaust pipe so you are monitoring both banks ie both the left and right cylinder heads, all the computations have already been programmed into HP Tuners by their programmers, and after tuning the PCM will use these stock narrow band sensors to operate anyway, not the wideband, etc.

CONS for all three choices above: you can not tune Wide Open Throttle (WOT) condition with this mthod, you are limited to only tuning Idle and Cruise modes aka the Closed Loop.

Option 2. Aftermarket Wideband Oxygen Sensor Method

PROS you can tune the entire operational spectrum with this method, Idle, Cruise, and Wide Open Throttle (WOT) so both the Closed and Open Loop.

CONS you have to buy (expensive) and install the wideband oxygen sensor, also if you only buy one you can only monitor one side of the engine, and anyone who's spent any time with engines knows often times both banks ie both cylinder heads do not run equally hot or efficient, (let's not fight, ha ha) and after tuning the PCM will use the the stock narrow band sensors to operate anyway, not the wideband, this is important to acknowledge because it takes under consideration how the stock OEM narrow band sensors have aged and degraded, etc.

Because this is a basic tutorial intended to wet your appetite for tuning we will be using the factory narrow band Option 1 above relying on both the LTFT+STFT special math function for the win! Nothing stops you from going at it a second time once you have a Wideband and confirming this tune and building upon it by also tuning WOT.

02-08-2020, 03:24 PM	#231
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,810	Re: HP Tuners Tutorials - MAF Scaling - Calibration MAF Scaling - Calibration You can calibrate the MAF in two ways, using either the stock narrow band oxygen sensors or using an aftermarket wideband oxygen sensor ie AFR gauge. Option 1. Factory Narrowband Oxygen Sensor Method To make things even more complicated, in this method you have three further choices: Tune using only the Long Term Fuel Trims Tune only using the Short Term Fuel Trims Tune using both the Long and Short Term Fuel Trims simultaneously PROS for all three choices above: you already own the narrow band oxygen sensors, you also have two of them, one in each exhaust pipe so you are monitoring both banks ie both the left and right cylinder heads, all the computations have already been programmed into HP Tuners by their programmers, and after tuning the PCM will use these stock narrow band sensors to operate anyway, not the wideband, etc. CONS for all three choices above: you can not tune Wide Open Throttle (WOT) condition with this mthod, you are limited to only tuning Idle and Cruise modes aka the Closed Loop. Option 2. Aftermarket Wideband Oxygen Sensor Method PROS you can tune the entire operational spectrum with this method, Idle, Cruise, and Wide Open Throttle (WOT) so both the Closed and Open Loop. CONS you have to buy (expensive) and install the wideband oxygen sensor, also if you only buy one you can only monitor one side of the engine, and anyone who's spent any time with engines knows often times both banks ie both cylinder heads do not run equally hot or efficient, (let's not fight, ha ha) and after tuning the PCM will use the the stock narrow band sensors to operate anyway, not the wideband, this is important to acknowledge because it takes under consideration how the stock OEM narrow band sensors have aged and degraded, etc. Because this is a basic tutorial intended to wet your appetite for tuning we will be using the factory narrow band Option 1 above relying on both the LTFT+STFT special math function for the win! Nothing stops you from going at it a second time once you have a Wideband and confirming this tune and building upon it by also tuning WOT. Last edited by Gregski; 02-18-2020 at 07:12 PM.