Open Loop Maf Tuning

[MMGT1]

I am wondering if intake temps are playing a role here? Are you tuning modifier tables too, or just the MAF?

[IndeedSS]

I am wondering if intake temps are playing a role here? Are you tuning modifier tables too, or just the MAF?

Intakes do play a role, especially here in the mid-west. Mornings low 50 degrees and afternoon 70+ degrees. However, I take those differences into consideration and don't tune around the extremes. Everything else being set to my satisfaction, I'm only talking about MAF table and fuel trims.

[MMGT1]

Are you using the function string to filter out 0% TPS or the fuel cell that you are in DFCO for? Sorry, just trying to narrow why you are getting such skewed #'s.

[IndeedSS]

Yes I've tried filtering by TPS and FTC. Since I'm always monitoring using dual Aeroforce gauges and the PLX WB, I can see why the STFT wouldn't make much sense to use. Even when seeing consistant and predictable 0 LTFTs, you can still watch STFT make compensating changes. Now if I were using the STFT variations by adding them to an already 0 LTFT to adjust the MAF table, then whatever that once 0 LTFT would now be off.

I guess all that really matters is that you get your LTFTs as close to zero as possible and are happy with the results. I just don't want anyone trying the STFT+LTFT to feel discouraged, if they are doing it correctly and not getting the expected results. In my mind there seems to be good reasons why this method may not be optimal for some.

[MMGT1]

Tuning cruise all comes down to what is delivered at entry to PE for me. If there are trims active at PE entry, it carries it all the way through your PE range. Dam V6 VCM's are a PITA!!

[Andy0x1]

Now the commanded AFR will be steady at 14.7. With the Maf AFR histogram open, drive the car at part throttle to fill the histogram up to ~7500 hz. Try to accel & decel smoothly. Then copy & paste the Maf error % histogram to the Maf table using paste special multiply by %. Once you get the AFR close to 14.7, then...

Do the L/STFT's not come into play using this method?

Actually - nevermind - I assume by setting the PE Enable to 0% that because PE is always enabled the Trims never come into play.

[Andy0x1]

Intakes do play a role, especially here in the mid-west. Mornings low 50 degrees and afternoon 70+ degrees. However, I take those differences into consideration and don't tune around the extremes.

Extreemes? It is currently 10 below here, are you saying right now would be a bad time to tune my car?

P.S. I didn't realize optimal A/F ratios were all that much different with cold v.s. hot intake air.

[Andy0x1]

I thought it was only for Spark.

Are you suggesting those with a "Happy knob" installed to adjust their ignition timing via a custom IAT table, that they are changing more then their spark when twisting the knob?

[Perforator]

Fuel and airflow go hand-in-hand. There is definitely an air temperature compensation factor for airflow.

[Andy0x1]

Colder air = denser air = needs more fuel for a given volume.

However I see no table related to this.

The MAF works via a heated element that is cooled by airflow. Colder air flowing over this heated element would result in a higher MAF reading right? If the volume is accounted for via the MAF, then the IAT sensor may only be used for spark tables?

Because I don't see anything in the editor related to fueling v.s. IAT, I guess either someone who reverse engineered the PCM or someone with a wideband that wants to do some experimenting could answer this.

[Perforator]

Just because you don't see them doesn't mean there not there.

[Andy0x1]

Nor does it mean that it is.

[Perforator]

Trust me, it's there, it's just not in the tuner.

[mourat]

I wanted to take the time to tune my drivability today, I have set my PE enable TPS table to 0, all the adder tables, and start up tables to 0, I set the commanded AFR to 14.7 across the board, set Closed loop enable to 140*C to it never comes on.

However, as I am logging, the status bit for PE enable is not "active" even though it should be acording to my TPS enable table being set to 0, and the commanded AFR fluctuates depending on my driving, rpm, etc... even though I set it to be at 14.7 at all times.

Therefore I am not able to run a MAF error correction Histogram pid as my commanded is all over the place, I have included a log of this event and also the HPL tuner file as well.

Is there something I'm missing, or is HP Tuners not saving the PE variables I'm asking it to or ignoring them somehow.

I read here everyone is tuning their V6 cars this way, the only thing I can think of is that PE is not being enabled if the car is not going into closed loop, I realize RK's write up says to disconnect the 02 wire to go into open loop, but is setting closed loop enable to a higher temp not the same thing?

Thank you so much in advance.

[umrjmac]

I wanted to take the time to tune my drivability today, I have set my PE enable TPS table to 0, all the adder tables, and start up tables to 0, I set the commanded AFR to 14.7 across the board, set Closed loop enable to 140*C to it never comes on.

However, as I am logging, the status bit for PE enable is not "active" even though it should be acording to my TPS enable table being set to 0, and the commanded AFR fluctuates depending on my driving, rpm, etc... even though I set it to be at 14.7 at all times.

Therefore I am not able to run a MAF error correction Histogram pid as my commanded is all over the place, I have included a log of this event and also the HPL tuner file as well.

Is there something I'm missing, or is HP Tuners not saving the PE variables I'm asking it to or ignoring them somehow.

I read here everyone is tuning their V6 cars this way, the only thing I can think of is that PE is not being enabled if the car is not going into closed loop, I realize RK's write up says to disconnect the 02 wire to go into open loop, but is setting closed loop enable to a higher temp not the same thing?

Thank you so much in advance.

Your log and tune didnt make it into your post, but read through this and you may figure out what, if anything, you missed.

http://ls1tuningguide.com/tuningmanu...ons%20rev3.pdf

[mourat]

Never a problem tuning V8's, but no matter what I do in the TPS HOT enable Table for PE, set it to activate on 0%, it only activates at 15%, so there is prolly a min tps table somewhere that is not in HP tuners for my particular version?

[SandmanGTP]

Going through this as a newbie I got a couple of questions just to make sure that I've gotten this right:

I've got the Power Enrich vs Fuel Adder vs. TPS, Hot Power Enrich Enable TPS Threshhold vs RPM, Power Enrich Fuel Adder vs RPS vs Time all set to 0 in all cells

Then the Power Enrich Fuel Base vs ECT set at 14.7

After driving around it says to do this:

Then copy & paste the Maf error % histogram to the Maf table using paste special multiply by %. Once you get the AFR close to 14.7, then use paste special multiply by % - half

Copy the maf error histogram and paste into the main VE table? What is paste special multiply by % - half?
to
Doing all of this takes car of the LTFTs from what I understand. Then I set everything back to stock and the PE Enable TPS to what I want correct?

Then for the WOT tune do pretty much the same thing just for the high freqs for the maf.

How do I get the car to lock into 2nd in the VCM? \

And all of this without the stock O2 of course.

Is all/most of this correct?

[TeacherCreature]

I am gonna play with some of these methods on my next tune.... I am wondering if it pays to turn off learn mode once the car is dialed in?

[WarShrike]

Here's the progress so far with my setup, anybody able to give me any pointers? Just doing first step atm, no WOT yet.

LINK: Clicky

[jabartram]

i need some help setting up a histogram for maf tuning on my 03 alero 3400, i watched the instruction video but im not sure what parameters need to be set. and im having trouble finding instructions on setting my w/b, it needs to be scanned also correct?