MAF Subaru: SGII reporting MAP?

[pickler]

hi people. i have a 2009 subaru impreza sedan and when i installed the SGII today i noticed that the MAP gauge is reporting a variable number?! i'm 100% sure my vehicle is MAF sensor equipped as it is the 08+ SOHC 2.5L. What is this number that it is reporting? Also has anyone had any success in getting the O2 sensor xgauge to work? thanks!

[CarlD]

Originally Posted by pickler

hi people. i have a 2009 subaru impreza sedan and when i installed the SGII today i noticed that the MAP gauge is reporting a variable number?! i'm 100% sure my vehicle is MAF sensor equipped as it is the 08+ SOHC 2.5L. What is this number that it is reporting? Also has anyone had any success in getting the O2 sensor xgauge to work? thanks!

MAP is manifold absolute pressure, or vacuum as it used to be called. Reporting MAP is expected, are you saying that you can't get a reading for MAF? Go to the CMNDS screen and enter 0110 into a memory and hit SEND. This should return a reading for MAF.

The scangauge actually requests MAF but I don't know why it wasn't made into a default gauge. Maybe legacy in that in the past few cars reported it but if that was the case FPR probably would've been axed also.

If your vehicle is CANSF, an xgauge for MAF would be:

TXD: 07DF0110
RXF: 044145100000
RXD: 2810
MTH: 000100010000
NAM: MAF

in grams/second

I think a lot of the A/F xgauges that they list on their site aren't correct, unfortunately.

[pickler]

thanks i tried that code but nothig shows up. i sent 0110 to memory and recieved this:

4110019d00000000

what do i do with this number? i really need maf to monitor results of intake mod and make sure its not reporting wierd numbers.

[CarlD]

Originally Posted by pickler

thanks i tried that code but nothig shows up. i sent 0110 to memory and recieved this:

4110019d00000000

what do i do with this number? i really need maf to monitor results of intake mod and make sure its not reporting wierd numbers.

The number you got back is 4.16 grams/sec. The numbers 0x019D = 416 and divide this by 100.

My mistake, the RXF is not correct. This xgauge should work:

TXD: 07DF0110
RXF: 044145100000
RXD: 2810
MTH: 000100010000
NAM: MAF

in grams/second

A rough approximation for airflow in CFM (asuming air density of 1200g/m^3) can be had by changing the MTH to:

MTH: 007100400000
NAM: CFM

[pickler]

thank you for this. now it works. by the way my AFR seems to be too consistent. its always around 14.6 and rarely does it go below. in full throttle on top gear it goes dowmn to 13.9 near 2500rpm. at wot in best gear i saw it only once go below 12. most of the time in wot im witnessing 13.5+. maybe my update rate is too slow. oh and when i take foot off gas it jumps to 20 for a few seconds!! i will video log this tomorrow but even during moderate acceleration afr is above 14. if this is true then im running way too lean.

[RedylC94]

Originally Posted by pickler

when i take foot off gas it jumps to 20 for a few seconds!!

Is 20 merely the highest number the display can show for AFR? If so, it seems that would be reasonable during fuel cut.

[CarlD]

Originally Posted by pickler

thank you for this. now it works. by the way my AFR seems to be too consistent. its always around 14.6 and rarely does it go below. in full throttle on top gear it goes dowmn to 13.9 near 2500rpm. at wot in best gear i saw it only once go below 12. most of the time in wot im witnessing 13.5+. maybe my update rate is too slow. oh and when i take foot off gas it jumps to 20 for a few seconds!! i will video log this tomorrow but even during moderate acceleration afr is above 14. if this is true then im running way too lean.

Try this xgauge for A/F; it should have a max reading of 20 and minimum of 9, which is the range the sensor can actually report:

TXD: 07DF0124
RXF: 044145240000
RXD: 2810
MTH: 0001003A0384
NAM: A/F

Obviously a reading of 20 indicates fuel cut. I don't understand the A/F xgauges on the ScanGauge website but this one should work correctly, but if not I would need to know what O2 sensor you have.

[pickler]

ok I will try this code tomorrow. almost everytime I look at the afr its always 14.3-14.7. will see how this does.

[pickler]

ok it works great now.

i was wondering if it was possible to tap into my TPMS with my scangauge 2 and read the individual tire pressures as well? is this possible? i mean my car can read tire pressure and display low tire pressure light.

[CarlD]

Originally Posted by pickler

ok it works great now.

i was wondering if it was possible to tap into my TPMS with my scangauge 2 and read the individual tire pressures as well? is this possible? i mean my car can read tire pressure and display low tire pressure light.

Perhaps, if the pressures are on the can bus. I know for Fords that they put this on the lower speed CAN bus that the SG can't connect to. How to find out the PIDs for tire pressure on a Subaru will probably be a challenge....