Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

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Olegonic
Posts: 22
Joined: Mon Aug 17, 2020 9:15 pm
Location: Russia

Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by Olegonic »

I’m new to the using Tuner Pro soft let along EEPROM emulator for online tuning of ECU
Yet, I rather understand what exactly I do need from my turbocharged M50B25 non vanos
The problem is any changes I do in fuel/ignition maps, don’t change engine performance and AFR
What those 128 numbers mean in the table (idle fuel map for instance)?
Also, I have stock lambda connected - would it not let me change the fuel map on idle, for example?
How should I remove lambda from ECU?
402 Bosch XDF doesn’t have flag lambda related in order to disable the latter
I’m using AEM X series UEGO wideband oxygen device
Garrett GT2860 at 0.7 bar boost
RPM are floating a while on idle after full or partial throttle off
Standard MAF before turbo
Mishimoto Z-line intercooler
Blitz SBC DC boost controller
9,7 CR

Many thanks for any constructive and usable input!
BMW E30, M50B25 NV turbo
olafu
Posts: 186
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by olafu »

Tell more about your emulator..? Did you have green based "emulating" text at the bottom of Tunerpro window?
Olegonic
Posts: 22
Joined: Mon Aug 17, 2020 9:15 pm
Location: Russia

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by Olegonic »

Yes I have green EMULATING text on the bottom left
When I change idle fuel map, for example, I save changes, message UPLOAD SUCCESSFULL, and emulator is beeping
BMW E30, M50B25 NV turbo
Olegonic
Posts: 22
Joined: Mon Aug 17, 2020 9:15 pm
Location: Russia

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by Olegonic »

https://www.instagram.com/tv/CHfzNOXJ8 ... q5u3woed07
I was able to change the idle AFR (reach/lean) by selecting the whole IDLE FUEL MAP and increasing/decreasing all values
Not sure if the rest of maps would work the same way, didn’t test on the road yet
BMW E30, M50B25 NV turbo
olafu
Posts: 186
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by olafu »

Looks like closed loop is active, but AFR should be around 14.7 then... :?
I think M3.1 has similar "emission stage" flag than M3.3.1 has, but unfortunately anyone wasn't put it in the XDF file. If you got diagnosis scanner, you can see if closed loop is active.
Those table values are fuel corrections. In M3.3.1 128 means no correction, so multiplier is "1". Value 0 means multiplier is "0.5" and 255 means multiplier is "2". I guess M3.1 has similar principle.

So, what next? I think next step is find the way to switch closed loop off, but i can't surely say how.
Olegonic
Posts: 22
Joined: Mon Aug 17, 2020 9:15 pm
Location: Russia

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by Olegonic »

Important correction - I had lambda terminal removed
If lambda is connected, DME will correct the AFR no matter what you’ve done with map
BMW E30, M50B25 NV turbo
Olegonic
Posts: 22
Joined: Mon Aug 17, 2020 9:15 pm
Location: Russia

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by Olegonic »

Can someone PLEASE edit or change existing XDF for 402 DME in order to have an option/flag to disable oxygen sensor?
BMW E30, M50B25 NV turbo
olafu
Posts: 186
Joined: Tue Jul 26, 2016 12:35 pm
Location: Finland

Re: Soo, anyone succeeded on tuning/changing fuel/ignition maps on 402 DME?

Post by olafu »

You can try to find it, if you have diagnostic scanner which is capable to show if closed loop is active or not. I think the O2 bit is somewhere in 0x6B02 - 0x6B20. Plug o2 sensor back and let engine idle and warm up. So the closed loop o2 control switches on.
Try to change those bytes to "00" and then "FF" by one at a time, and see what happens. If nothing happens, set the byte back to original, then go to next byte. If your scan tool shows the closed loop switches off by changing some byte, then split that byte to bits and try to switch separate bits to 0 or 1, depending if the whole byte was 00 or FF. 00 means all bits are "0" and FF means they all are "1"

Warning: In theory it is possible to break hardware by modifying those bytes or do something else by "shooting to darkness". I never blew anything from my M3.3.1, but i think it is possible, and M3.1 can be different... But so, if engine starts misfiring or ecu crashes, immediatelly switch ignition off (also coil damage is possible, if ecu leaves primary current on). Then set parameter that caused crash back to original. If engine doesn't start, plug ecu connector off or battery main switch/cable off and wait. It can take up to 15 minutes to reset SRAM. If engine still doesn't start, you was propably blew your ECU :(

A couple of times i get my M3.3.1 crash so totally so it had to be reset by unplugging it from battery power.

But this is only way without full code disassembly, if anyone can't tell where is this flag.
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