413 MAF on 402

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RaimoHal
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Joined: Tue Apr 08, 2014 12:22 pm

413 MAF on 402

Post by RaimoHal »

Hello!

Has anyone done this with a success?

I copied 413 maf table to 402 ecu, but the car falls on its face when i try to accelerate. Is there a MAF plausibility/voltage thresholds on 402 ecu?

From the testing that i have done, the 413 MAF signal is about 0.4 - 0.8v lower than 402 maf on low rpm and load.

Thanks!

olafu
Posts: 145
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: 413 MAF on 402

Post by olafu »

How did you copy that table?

402's -599.bin's XDF from tunerpro site has no conversion, but 413's -623.bin XDF has some conversion.

Try to use "Show raw hex" (right click table and set "Show raw hex" on.) and then try to copy-paste.
I'm never tried to change MAF sensor, but if -402 dme has similar code for MAF voltage reading than -413, there is no voltage limits to MAF signal, so plausibility checks and limits are based on table values.

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RaimoHal
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Re: 413 MAF on 402

Post by RaimoHal »

I did a copy-paste in winols and im using X/4.6 conversion in tunerpro on both tables.

I think i missed something when copying the 413 table. On 413 ecu, the last value is shown as "00" @ 5V maf voltage, but for the 402 ecu, the last value is 906kg/hr. It looks like maps are shifted by one. I need to fix it and see if that makes a difference, but i doubt it.

Top one is 413 maf and bottom is stock:

Image

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RaimoHal
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Re: 413 MAF on 402

Post by RaimoHal »

I did some testing with the MAF input on the ecu. The maf was removed for the testing and i was using a piggyback ecu to emulate the maf.
Im sure that there must be some sort of limiter. PT/WOT @ 3200rpm and maf signal of 3,8v, it cuts fuel and maybe retards ignition. PT/WOT @ 3200rpm and 3.5v maf signal its fine. I have my AFR gauge fitted and i know that it cuts fuel. The fuel ecconomiser also goes to 0.

Right now im trying to figure out if there are some limiter table(s) around MAF map.

olafu
Posts: 145
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: 413 MAF on 402

Post by olafu »

Warning, these are for -413 ecu:

Stock -413 ecu has (at least) three MAF plausibility limits, based by MAF table values*:
- absolute flow minimum value (16bit)
- absolute flow maximum value (16bit)
- RPM dependent maximum flow value (looks like flow values divided by RPM). *

Maybe there are similar limits, but for raw ADC in -402 ecu. I don't know, but it's technically possible..?

* I tried to change maf "flow" by using voltage divider to produce MAF signal. I noticed there is no any voltage limits to MAF signal, everything is based by MAF table. MAF signal short to ground: Ecu reads first cell from MAF table, and if table value is plausible for actual conditions, there is no fault codes and ecu works like there is some real MAF voltage from sensor.

*EDIT* corrected: rpm dependent maf flow limit is not 2d curve, it's fixed value.

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