Axis descriptor for 402 xdf

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gavin
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Joined: Fri Dec 25, 2009 8:10 am

Axis descriptor for 402 xdf

Post by gavin »

Hi i'm trying to learn more abaut motronic map, what will be the descriptoion and formula for:
C1
CB
CE
CF= load MAF?
D1
D2
D3=Volt?
D4
D5=RPM?
D6
D7=engine temp?
D8
D9
please HELP!!
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aboutton
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Post by aboutton »

Just ask for it :

CF RPM
21 Throttle position
D4 Air temp
D5 Load
D6 Air Temp
D7 Coolant
D8 BATTERY VOLTAGE
D8 Voltage
gavin
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Post by gavin »

what about formulas ?
i know only how to calculate RPM
CF 10 05 08 0a 0c 08 0b 0a 0a 09 0a 0c 0a 09 06 0a 60 Hex
27 16 5 8 10 12 8 11 10 10 9 10 12 10 9 6 10 96 Dec

formula :60 Hex = 96 Dec
(96*40) -(256*40)
and that give 6400.

so now we have Dec: 5 8 10 12 8 11 10 10 9 10 12 10 9 6 10 6400


the next value is on the left !
But from there we will only substract from the right :
10 hex = 10dec
and we do 6400-(10*40)=6000

What are the formulas for the rest?
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aboutton
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Post by aboutton »

for RPM limiter, data is hex(90 65) you must swap the 2 bytes gives you hex(65 90) change to decimal gives you 26000 /4 = 6500

NB: to swap the bytes click on LSB first

for ignition tables
The factor for RPM is 40, and the offset 0. For the Load the factor is 0.715, the offset is 0.
The factor for the ignition advantage is 0.75 and the offset is -22.5.
example: ignition advance = ( data * 0.75)-22.5

D4 Air temp factor 0.75 offset -48
D5 Load factor 0.715 offset 0
D7 Coolant factor 0.75 offset -48
D8 Voltage factor 0.068 offset 0
21 Throttle position factor 0.5625 offset 0
CF RPM factor 40 offset 0



:) what else you need to know ? how to create 2 switchable maps for your car ? wanna make launch control ? shifting light ? even make 402 ecu control Vanos ? make the car run without air mass sensor ?.... just name it....
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aboutton
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Post by aboutton »

NB: Injection maps are not really injection maps rather then injection correction maps.
value 128 = no correction
the ECU will calculate required fuel from load and TPS and finds out how much fuel is required, the table will correct what the ECU injects.
so bottom line it is not a real fuel table.
gavin
Posts: 59
Joined: Fri Dec 25, 2009 8:10 am

Post by gavin »

aboutton wrote:for RPM limiter, data is hex(90 65) you must swap the 2 bytes gives you hex(65 90) change to decimal gives you 26000 /4 = 6500

NB: to swap the bytes click on LSB first

for ignition tables
The factor for RPM is 40, and the offset 0. For the Load the factor is 0.715, the offset is 0.
The factor for the ignition advantage is 0.75 and the offset is -22.5.
example: ignition advance = ( data * 0.75)-22.5

D4 Air temp factor 0.75 offset -48
D5 Load factor 0.715 offset 0
D7 Coolant factor 0.75 offset -48
D8 Voltage factor 0.068 offset 0
21 Throttle position factor 0.5625 offset 0
CF RPM factor 40 offset 0



Smile what else you need to know ? how to create 2 switchable maps for your car ? wanna make launch control ? shifting light ? even make 402 ecu control Vanos ? make the car run without air mass sensor ?.... just name it....
Great work jedi master :D
But this does not answer my question completely.
How to translate values in Hex like this 1e 1d 1e 1d 15 in to voltage Volt
or hex 01 09 15 01 4f 14 01 2f in temp C
or Hex 17 0f 08 bb in air temp C
And yes i will love to have launch control on e30 with m50 engine or ride without MAF or lambda.

aboutton wrote:NB: Injection maps are not really injection maps rather then injection correction maps.
value 128 = no correction
the ECU will calculate required fuel from load and TPS and finds out how much fuel is required, the table will correct what the ECU injects.
so bottom line it is not a real fuel table.
So you say that when i will disconect MAF i will be eable to have more control over the ECU fuel delivery?
All my problem will be solved i will always have AFR how i wont it no matter what?
Right now my bigest problem is that when i set values in WOT map to have good AFR ECU make changes after some time.
Second problem is that engine is shaking on iddle when it gets warm,and the AFR jumps from 13.5 to 16.9.
Henn0
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Post by Henn0 »

when you disconnect the MAF you will have the engine going in to "Alpha N" mode. in practice this means that the ECU calculate/estimate load using RPM and throttle position. From this the ECU determin the correct fueling based on ingoing air temp and load.

in relation to the MAF + IAT meassurment of load, this is not as precise meassurement of load. altough, you can benifit of greater response if the tune is done correctly. You will also be able to get more air-flow into the engine when the MAF is deleted.

Alpha N is not well working with force induction.

the 402 have a Alpha N map wich is a back up to the MAF, this can be tuned to work pretty good. I am working on this for my car right now, a bmw 2002-73 with m50b25 and a alot of other mods.

I can give you the adress if you would like to try your self :D

aboutton: I would realy like to know how to add features to the motronic 402, as for the launch control and 2 maps switch lights etc, do you also know where to find the Cranking fuel Map? this is my biggest concern right now.

to stop the ECU from making changes, I would recommend you to unconnect the Lambda-sond, and then set all the Lambda maps to 0.

search for the Motronic m3.1 guide at ecuconnections.com, there you will find all the info your are asking for and some more :)
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aboutton
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Post by aboutton »

Henn0: Sorry for replying too late but the race season has began.

for cranking fuel map try : 0x71F3 ( 3 x 1 map )
axis value : 160,360,720

Im having a problem with 402 turbo, if you think you can help PM me.
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