Open Loop Maf Tuning

[PWNED]

I am going to be attempting your open loop maf tune. If I get this right when all said and done with the tune I want to set

PE enable>delay vs. tps = zero out which it is stock
PE enable tps>hot = where I want it 20%.
The base afr vs. ect to 11.50 since I'm supercharged to be safe @ 11.7 now
Zero out the add vs. rpm table.

What about the add vs tps? Do I leave this zeroed out? Are there any pros or cons of having this and the add vs rpm zeroed? Just curious on what these changes do exactly.

THis is on a 99 GTP (s1x,48#,3.4,headers,cb)

[MMGT1]

I would leave it 0'ed out. If I find the an engine is going lean at all in the top end then you need to hook up the wide band again and make adjustments to the maf table in that region to get your desired AFR. There are tuners that use only that table to tune fuel and leave the MAF stock. I say, choose one or the other and stick with it. Having both tables interact to tune that area is a pita in my opinion. Just make dam sure that a WB is being used to adjust your MAF table in PE. Just telling the car to go to 11.5 in desired AFR wont cut it, it has to be verified with your WB. 20% TPS for PE is a might bit low too I have to say. You will bounce off 20% with minor TPS changes at highway speeds. PE that low is going to kill your NB Sensor pretty quick, and waste a lot of fuel in the long run. Try tuning PE for the area of 30-35%. Just my 2 cnts

[Isaak]

Ok I am having some issues, I must be missing something, because when I attempt to do my maf tuning, I get nothing but 0's across the maf board.

Here is a scan, and more importantly my file being used.

Any help is appreciated!

[Ace25]

Isaak, this might be a bit late, but it looks like you need to add the MAF freq error to the primary table in the VCM scanner.

- Open the scanner with the default imperial config
- Displays - table - primary - right click an empty spot and insert Mass Air Flow (freq error)
- Go into histogram config and select histogram 3: VE Long Term Fuel Trims
- Change the name to MAF - LTFT
- Click on Row & Col Axis
- Click on the Primary VE... under the Table header in the Primary section
- Scroll down to MAF Airflow VS Output Frequency and double click

- Open the table display
- right click an empty field and insert the engine/airflow/Mass Airflow (Hz) PID

- Save the config as whatever you like (EG: Default MAF.cfg)

[Ace25]

I have an LC1 permanently installed, so I'm assuming I can go to the "Open & Closed Loop" tab & set the coolant temp to 284F (so that closed loop doesn't enable)

I have my PE - Fuel Base vs. ECT all set to 14.7, I noticed the "open & Closed loop" OL AFR vs. Coolant temp. Should this be set to 14.7 across the table as well???
screen shot here:
MAF.jpg

[Russ K]

I have an LC1 permanently installed, so I'm assuming I can go to the "Open & Closed Loop" tab & set the coolant temp to 284F (so that closed loop doesn't enable)

I have my PE - Fuel Base vs. ECT all set to 14.7, I noticed the "open & Closed loop" OL AFR vs. Coolant temp. Should this be set to 14.7 across the table as well???
screen shot here:
MAF.jpg

Yes, set the CL to 284*F. Set your PE richer than 14.7 (11.0 AFR boosted or 13.0 NA), and the OL table to 14.7 at operating temp.

Russ Kemp

[Ace25]

Yes, set the CL to 284*F. Set your PE richer than 14.7 (11.0 AFR boosted or 13.0 NA), and the OL table to 14.7 at operating temp.

I was initially confused by this... To clarify, I think I should leave the PE at 14.7 for doing the first part of the tune, under 4,000 RPM & under 50% TPS for the lower MAF cells; then when I move on the WOT portion, I need to set PE Richer to 11.0 for my boosted engine?

[Russ K]

I was initially confused by this... To clarify, I think I should leave the PE at 14.7 for doing the first part of the tune, under 4,000 RPM & under 50% TPS for the lower MAF cells; then when I move on the WOT portion, I need to set PE Richer to 11.0 for my boosted engine?

That method was before we had the open loop tables.

Russ Kemp

[Ace25]

So, with the newer open loop table that we have, there is no need to tune the lower half of the MAF frequency & the upper half separately? I'm assuming that with the OL table commanding 14.7, that is good for the lower feq cells and that the PE commanded at 11.0 will protect the engine at WOT.

In summary, then, we can now tune the entire MAF range? Thanks again for your help!

[Russ K]

So, with the newer open loop table that we have, there is no need to tune the lower half of the MAF frequency & the upper half separately? I'm assuming that with the OL table commanding 14.7, that is good for the lower feq cells and that the PE commanded at 11.0 will protect the engine at WOT.

In summary, then, we can now tune the entire MAF range? Thanks again for your help!

You got it right.

Russ Kemp

[Ace25]

This is like learning how to ride a bike; Thanks for being a mentor Russ! Before tuning, my LTFT would lock at -2.3 at WOT; now they lock at 0.0 (regular driving seems to have much better LTFT too; (the verdict is still out on the STFT though, i've heard some people ignore these??)

One other odd thing I noticed; the car seems to do better in Open Loop then closed loop The most I saw KR in OL was 0.4 or 0.5; CL has it up to 1.5. I was also able to run leaner in OL before PE would enable (better mileage) for normal driving.
MC 6-14-13-MAF run3.hpt (tune used in OL for MAF calibration)
Maf initial scan3.hpl (scan of above MAF calibration)

05 MC SS - June2013-tune1- After MAF.hpt (Current tune after MAF)
after MAF tuning.hpl (Current scan of "after MAF" tune)

Attached is the tune / scan while in OL & then the current hpt file that I'm running after the MAF tune, along with a post MAF scan.

The next goals would be to get rid of that KR & then lean things out under 2500 rpm; (no cat to worry about) Any advice on this? I'm off to go search / read / search read & then repeat...

[Isaak]

I had it working last year, but when attempting it now, it is zero's again! I must be missing something easy!

FTTUNE (TUNE).hpt
july9fttune.hpl
Isaak.cfg
tune.cfg

Isaak, this might be a bit late, but it looks like you need to add the MAF freq error to the primary table in the VCM scanner.

- Open the scanner with the default imperial config
- Displays - table - primary - right click an empty spot and insert Mass Air Flow (freq error)
- Go into histogram config and select histogram 3: VE Long Term Fuel Trims
- Change the name to MAF - LTFT
- Click on Row & Col Axis
- Click on the Primary VE... under the Table header in the Primary section
- Scroll down to MAF Airflow VS Output Frequency and double click

- Open the table display
- right click an empty field and insert the engine/airflow/Mass Airflow (Hz) PID

- Save the config as whatever you like (EG: Default MAF.cfg)

[Russ K]

Your in open loop, and the B1S1 is stuck at 447 mv. Lower your closed loop enable temp, you have it maxed.

Russ Kemp

[Isaak]

Your in open loop, and the B1S1 is stuck at 447 mv. Lower your closed loop enable temp, you have it maxed.

Russ Kemp

Because I disconnected my O2 sensor (I have a wideband installed).

[User007]

is the commanded afr at idle supposed to be 13.7 because that what mine is showing even though i set the pe af vs ect tables all to 14.7

[MMGT1]

Post your current tune, you've probably missed an adder somewhere

[User007]

here the current one

[MMGT1]

Fuel/Open and Closed Loop/Under Open Loop/ O/L AFR... set those to 14.7
Then right next to it, AFR Adder... 0 it out for tuning O/L

[User007]

okay thanx, so there need to be changes to 6 tables. The two that you mention and the ones under PE:

Base PE A/F vs ECT, PE Delay vs TPS, PE Enable TPS, PE RPM vs Time A/F
Correct?

[MMGT1]

Yes, you got it. Just set your C/L temp to a value it will never see.... max it out. And also remember to set your EGR to max for tuning, then you can re-enable when your done. It is worth having the EGR enabled for the mileage you'll keep from it after, but that is definitely a preference thing, your choice.