Auto MAF (the begginning)

[kwhiteside]

So I've done my first AutoMAF log. The 2700-3300 range of the MAFFREQ/Ben Map kinda scare me.

Just to review my process first to make sure I'm doing it right.

b0120 set to 400 so I'm in PE mode all the time.
b3801 disabled, no LTFT
Logged MAFFReq in addition to my other PIDS
P0101 - p0103 set back to MIL
DFCO temp set real high to disable

Opened Log, then opened the B5001-MAF Calibration - LC1 WO2 BEN.map sample file. Change LC1 to my WO2AFR Ben and voila, my map filled in. See pic. I've also included my tun and log.

So I'm supposed to copy with labels, then paste and multiply with labels over the top of my B5001 right? What about those really high multipliers from 2700-3300?

What does the MAF Calibration LC1 WO2 AFR map do for you?

My car ran decent expect idle at stop got down to 500rpm. Makes you worry your gonna die out. That is probably another chapter later though.

Ken . . .

[mr.prick]

What does the MAF Calibration LC1 WO2 AFR map do for you?

It does the same thing that the VE WBO2 map did.

Despite what the the description tab for B5001 says,
after changing the VE table the MAF will need adjustment and
an across the board increase is not abnormal.
If you are going to enable LTFTs and changed B0101 with just WBO2
then don't waste your time with the MAF and WBO2.
FYI
B0120 sets the PCM to use the MAF sensor exclusively for airflow above it's value, not enable PE.

[5.7ute]

So I've done my first AutoMAF log. The 2700-3300 range of the MAFFREQ/Ben Map kinda scare me.

Just to review my process first to make sure I'm doing it right.

b0120 set to 400 so I'm in PE mode all the time.
b3801 disabled, no LTFT
Logged MAFFReq in addition to my other PIDS
P0101 - p0103 set back to MIL
DFCO temp set real high to disable

Opened Log, then opened the B5001-MAF Calibration - LC1 WO2 BEN.map sample file. Change LC1 to my WO2AFR Ben and voila, my map filled in. See pic. I've also included my tun and log.

So I'm supposed to copy with labels, then paste and multiply with labels over the top of my B5001 right? What about those really high multipliers from 2700-3300?

What does the MAF Calibration LC1 WO2 AFR map do for you?

My car ran decent expect idle at stop got down to 500rpm. Makes you worry your gonna die out. That is probably another chapter later though.

Ken . . .

Ken, did you set C2901/C2903 back to stock to reenable the maf?
Edit: just checked your tune & it was set back to stock. Doh

Also make sure you are filtering out the transients & low throttle positions etc. These are what will be giving you those high values from 2700-3300.

[kwhiteside]

What would be the filter to get rid of transients, TB > xxx % ?

I think I have DFCO enabled, set to come on above 86f. Is that right or wrong? I thought I set something to turn it off, but then I see this setting.

So much to learn, I thought the MAF was PE since it handled everthing over 4k rpm.

You know why I'm digging this stuff so much? Here it is.

I've been a programmer for my whole life. Building software and cogs that are challenging, but not nearly as satisfying as when I painted cars on the side. Everytime I handed over a car, it was quick satisfaction that was pinpointed to a brief period of action. Tuning seems to me to be a cross between the two. It's kind of like programming where you have to learn a lot of variables and manipulate them to get the results you want, but the thrill of driving you work, or a buddy driving your work, is like that painted car. The more difficult it is to achieve, the more pride you can take in the results.

Sorry for the rambling. I really appreciate all you guys helping out the newbies like myself.

[5.7ute]

I remove any data where TP is less than 1%. DFCO can stay turned on, just make sure you lift your foot straight off the throttle in Decel to allow the filter to remove this data. Slow steady acceleration will help to gather good data as well.

[kwhiteside]

Bare with me guys. I've been trying to get my mind around what is happening here. See the pic below. I went ahead and hardcoded the huge multipliers to 2, figuring if they need to really go higher, the next few runs will keep making that happen.

Correct me if I'm wrong here.

My wideband is reporting that during that ugly red range, I'm really pumping 3,4,5 times 14.67 into the engine (Extremely Lean). So by using the BEN multipliers to tweak my maf settings, I'll be telling (correcting) my MAF that for these ranges you are really pushing a lot more air than you think. AFter I make those changes, the net affect will be ( for the cells I hardcoded to 2x) half as much air, therefore a much richer mixture?

Oh, and just to make sure, 1500 MAFFREQ represents idle closed throttle and the bottom is full throttle?

One more thing. The fact that I have went from 78mm throttle body to a 90mm Tb, and also put a fast92 intake manifold should affect my maf how? It thinks the air passing thru it is being handled by the stock intake and a 78mm TB. Could this be why it is so far off?

[WeathermanShawn]

Ken, are you sure those MAF Frequencies you have highlighted are being filtered for DFCO?

I know you are keeping DFCO on while logging, but those values seem very odd. Just make sure when you filter, you filter out DFCO. You can filter it via throttle %, or better yet, any AFR over ~17.0 or spark advance of less than 10 degrees.

Your original columns are MAF Hz vs g/s. What are the second column values representing (chart on right)?

In calibrating my MAF, all my g/s calibrations increase for every Hz. I think it has to work that way.

[kwhiteside]

Ken, are you sure those MAF Frequencies you have highlighted are being filtered for DFCO?

I have the 6% TP Change filter applied

Maybe I missed it, but your original columns are MAF Hz vs g/s. What are the second column values representing (chart on right)?

The chart in the pic right above this post was using AFR instead of BEN, so when it reads 52, or 58, or 61, that is reported AFR :(

Now you will understand my concern with those ranges and bumping those numbers up as high as suggested. If you go up to my first post, you will see the suggested multipliers are 3.4 to 4 times. Nobody had chimed in, so I hardcoded to a max multiplier of 2 to be safe.

Now that I think about your comment of filtering out everything above 18, and reflecting on what happens to my AFR in my logs when I let off the gas, I think those values are from letting off the gas, and are very erroneous. My logs show my AFR going thru the roof every time I push in the clutch and let off the gas.

Any input would be great.

[joecar]

In your transient filter exclude TP less than 1% or 5% (i.e. closed throttle) and when driving/logging take your foot cleanly/smartly off the throttle pedal as 5.7ute said (might be easier if you disable DFCO during tuning since the PCM doesn't provide any real indication of DFCO active).

You will need to also filter out any AFR's greater than 15.00 say... and if you can log CPP (clutch pedal position, or whatever it's called) then filter out clutch disengagement too.

Your TB/intake may change MAF flow a little... so your MAF table may need a little adjustment... but only a little... 2x is too much.

(btw: the VE table is more meaningful when its units are g*K/kPa rather than %, but that's up to your preference).

[mr.prick]

If DFCO is on turn it off.
You may need more fuel in the VE table for that MAFFREQ range.