How to tune ms41 ECUs (BMW m52/s52 engines): basics 

If I was in Finland right now...ahh man....i would buy you a beer and a big steak :) Great video, and not just this one, all of them. Your knowledge is superb. Greetings from Serbia.

Thanks guys! This information is exactly what I needed. Once again thanks! :)

Wow, just wow. We appreciate your videos! This channel right here gives so much explanation about bmw's we mostly do our racing in baltics and helps putting more power into them. Giving DIY guys chance to do more with less money. Thanks alot!!

Thanks for all King PAZI! Greetigns from Portugal !

great job! Thank you from Kazakhstan! English subtitles save me life ;)

Great video thanks. I'm doing an m52tub28 swap into a 99 e46 318i sedan and interesting in mild tuning to increase rev limiter. Thanks from New Zealand.

What a fantastic video. Hats off to people like you.

Thank You! sooo much great info. I have been trying to work out how to do this for a while but couldn't work out what the deal was with my Australian delivered hardware - then I stumbled across your videos, and here is all the knowledge I need!! Very much appreciated :D

thanks alot @pazzi88 garret turbo m52tub28 e46 is coming along here in Canada

thank you for responding. ...I'll be in touch

Very valuable info. Thank you so much!

this is so good please keep these kind of videos coming. i live in Australia and am English speaking but have been watching your videos for sometime now. the subtitles help a ton but you also explain things so well :D

Thank you for this great video. I'm learning so much my head is exploding right now :) I actually just want to turn things in the ECU "off" ABS, DSC, airbags, downstream O2 sensor etc. I have a 2000 Z3 2.8 in the USA. I assume that's in the "Control Bits" at the top of the list?

Hey pazi, first I have to thank you a thousand times for sharing your knowledge and experiences! Your videos are extremely informative and helpful! Whenever I build my own turbo Bmw, I will mention you in some video! I haven't had the time yet to watch all of your videos but I will have to, there is nothing more interesting. But I already know some stuff about the different M5x engines and turbocharging them. But since you are the one with the experiences... I want to build an E36 turbo. I plan on using as many OEM non-M parts as possible to keep it as low budget and fun as possible. I thought about 450-500hp on 102oct pump gas since we don't have E85 anymore in Germany. What do you think would be the engine to go with whilst keeping as many parts stock as possible? M50B25nv, M52B28 or maybe M54B30? Looking at stock internals, DME, head gasket and maybe possibility to lower CR like milling the pistons for example. What do you think of maybe M54B25/B30 or M52B28TU which is similar to M54? I think downside of M54 would be rods. But boost limited to maybe 100Nm per rod should be ok, shouldn't it? And I've read that M54 has factory MLS headgasket. Also dual Vanos and good DME. M54B30 has some problems with weak piston rings and fewer cooling passages in block due to ULEV emissions stuff, but M52B28TU would be the easiest solution for around 450-500hp and around 600Nm, what do you think? How is valvetrain, pistons, rods and headgasket in comparison to M50nv and M52? Could I keep stock camshafts and make them fit for turbocharging via Vanos setup? Thanks a lot!

amazing video I can't wait to start my Frankenstein E39 project tuning stock ecu. I estimate ill get to about 850ft lbs of tq @ 5k rpm

Thank you! Great video as always. I will join the romraider forum and see if someone has anything already made for M52B25!

Dear sipa thank for your videos and bmw education! cheers from Mauritius Island

You are doing a really great work and helping a lot of people you are going to get intro car enthusiast haven :))

Great walk-through! Would be awesome if you did video on SAP delete

Can you make a video how to tune ms41 that shoots backfire catless

Yes I know. I have extra hole in my rear muffler :D

try to modify the obd2 connector, the same way you did, but both of the obd2 connectors that I have are wired the same... you said to jump #14 and #18 on the obd2 connector, I missing something? can you please explain? where did you get your obd2 connector or do I need to rewire the obd2 connector?

Thanks for sharing your knowlegde !! Very good video !!

Hi Pazi88, first up thanks for taking the time to make these helpful and informative videos, I'm hoping you - or indeed anyone - can help me out with a small issue. I have the K-Line cable with the appropriate 232RL chipset. I have the OBD2 to OBD1 converter, which already came with the pins bridged, and I am using the MS41 QuickFlash program as you recommend. Anyway, I can read the maps fine, do my comparison, edit and save the map OK using RomRaider, but no changes are being made to the map. Now I am aware on the OpenMS41 site there is a page regarding enabling write access, so I am assuming this is the issue - but the instructions are a little vague. it says: 1. Locate the x20 Diagnostic Link Connector near the RH strut tower in the engine bay and unscrew the cover. 2. Use a small piece of wire to connect Pin 14 to Pin 18 to put the ECU in Write mode. 3. Use a small piece of wire to connect Pin 2 to Pin 17 to bridge the OBD2 port in the car to the ECU. 4. Turn the ignition on, and use MS41 Quickflash to read/write the ECU. So I have the following questions about that procedure... Firstly, does Step 2 have the same effect as bridging pins 14 & 18 in the OBD1 converter cable? Second, is step 3 relevant on a UK car (Z3 2.8, 1997) that as far as I know has no OBD2 port in the car? Third, is bridging those pins with the ignition off sufficient, or do I need to cycle the ignition, then remove them, then plug the cable onto the round socket? If this isn't the cause of my problem, what else am I doing wrong? I feel like I am 90% close to completing my first ECU remap but I am stumbling at the last hurdle! Any help gratefully appreciated!

Nice video (as usual), thumbs up! As said often, avideo about fitting the E34 rear axle in the E30 would be very interesting, I'm sure I'm not the only one who's interrested in ;)

How do we find the software version???

Awesome video! How does one tune the MS41.1 for forced induction? Can you cover that as well?

That's great info! Can we disable EWS, is there a problem not running a speed sensor to the ECU? it would be great if you could do a video about swapping a m52 and using the ms41.

Hey that round obd adapter with the switch to enable write acess) were can i find it? the link to it is dead..

THX for tutorial. Can you make another video about how to tune ms41 ecu for fast deceleration "popcorn mod" ?

NICE JOBE byt whene you adepte a turbo do you need to programe the ecu

Hi, What is “Engine Speeed Limiter (Resume Delay)” ?? What effect does it have on rev limiter and how to adjust it? I have read the romraider table description but I couldn’t understand. Thanks.

Thank you for the information. I remap ms41 to support 7k rev and I encountered a problem that the engine can rev to 7k stay in idle but when I running on the road and every time I push rev over 6k then the engine check light on and into the limp mode . Do you know how to solve the problem. Much appreciated. This car was AT to MT swapped.

Absolutely fantastic videos! I have an ADS to serial port connector I use for inpa, would that cable work with open ms41 as well?

excellent video, I see in your comments about ews delete but I can't seem to find any option to do this, could you help?

Can flashing be done from inside the car via the ODB2 port if a switch is wired into the data link's 14&18 pins?

Hi dude, great videos, could you possibly do one on the control bits section and how to convert from decimal to binary and then back again?

I swapped my 97 e36 US m52 from auto to manual. What settings do I have to change or download to get the check engine light off and driver properly?

Is it possible to delete/diable EWS2 imobilizer with this? Haven't found any good answers on forums, and EWS can be annoying when swapping engines with EWS into a car that doesn't have EWS wiring. :D

really i cant thank you enough for this valuable information..... but how can anyone choose between this and buying aftermarket ecu..... i mean what is proc and cons of both of them?

Thank you very much

Hey Pazi quick question. After doing a partial write of the original file, the pops and bang and 7.000 rev limiter is not on. The write goes by the book and finishes 100%. What could the problem be? MS41.0 523i 1996 401

can i tune an ecu with index from m52b20 take this ecu wire on m52b25 head with m50 block that there is m54b30 internals and s52 cams n/a tuning will it work?

Hi Pazi88, can there be any difference in the ECU map between the iron block(US) M52B28 and alu block(EU) M52B28? My wire harness, ECU(MS41.0) and everything is from an EU car which originally came with an Alu block. Now I have changed it to a iron block which I imported from US. Head and harness is from the old EU engine. Wire harness modified to support the rear mounted crank sensor. I heard that some US cars change(direct plug and play) their ECUs to MS41.0(EU ECUs) in their Iron block cars saying that they are less restrictive than US maps in MS41.1 ECUs. May be because of O2 sensors and emission regulations. So, will their be any issue if I use the same MS41.0 ECU with the same map which came with the Alu block with my new iron block? Like in the knock maps between Iron and Alu blocks. Thank you in advance for your valuable feedback.

very good explanation!!

Mikähän ohjaus mahtaa olla -99 e36 320i? Mahtaako pysyä kärryillä minkäänlaisilla ahdoilla vakiona?

The link for quickflash does not work.

awesome video

I want to know English or your language to understand this. I'm from Spain and I have a bmw e36 with the engine broken, and I follow you from the 1st video that you uploaded on how to put turbo.

Sweet Video! Have you ever used the galleto 1260? I'm just curious because I've done everything that OpenMs tells you to do(solder the pins, software, xml file, definitions ect ect) right at this moment all I'm looking to do is log, but the tool doesn't connect to the car, any ideas?

Hello Pazi88 your videos are very informative love watching them! I have a question maybe you can answer. I have a ECU which is already mapped, however i would like to delete the EWS when i try download the map file from the ecu i get access denied by ecu B0. I have tried a orginal ecu with no map and it worked fine. I am using ms41 flash tool. Is this something you have come across?thanks

ok, even though my #14 has a black wire, I have to jump it to #18? correct? I can put a on and off switch between #14 and #18 and that should do the trick...

so since you're using romraider for tuning would the tactrix cable work on the bmw?

Hei! Kiitokset Sulle..saimme säädettyä e36 t.joutokäynti...oli muuten tehtaan säädöllä 90c°...n. 600rpm./min..sammahteli kun kytkin alhaalla käänsi ratista ajossa

thank you for sharingI'm having trouble with my romraider account activation and I need the ms41 ecu definitions is there anyway you can email me the XML or direct download link, any one can help please

Can you use this software to read CEL (check engine light) codes?

Great video! Could you make the same about ms43?

Pazi, I already have DCAN INPA cable, Do I still have to jam jamper pin 14 to pin 18 for read and write to my dme ?? ,,

Hi! Very nice video indeed! Is there a way to see if an ecu was tuned before? I'd like to find out if the previous owner did some changes... Thank you!

Can you use this for diagnostics? Reading and clearing check engine lights? If not what do you recommend?

What is the switch on the connector? Is that a bridge between 14/18 and 2/17 that enable writing?

Was wondering if I can turn off the EWS... if yes. can you tell me how? I have downloaded everything I need,but couldn't find ews....can you please help. ... Thankyou

ok, so there is a place on romraider, that says properties and open that? correct and just look for byte 8. what should I change it too? that would turns off the ews or deletes it?

thanks for the video!

Sorry, in this way the immobilizer and the speed signal that reaches the ecu is canceled. I asked him why I'm doing a swap e30 to m52b25 that comes from an e36 and the car has ignition but can not start

Hi pazi, I buy your OBD1 20 pin adaptator from your link but I don't have the switch to enable write mod ? Is it you who add the switch or it's a special cable ?

hello i don't know if you can read this so many years after, but i have strange problem, i did it like you showed it, partial readed- no problem. when i was trying to write it, it stops on 8%-says it's done, checksums corrected and car won't start. readed ecu again and the maps are not correct, still have the connection to the ecu, looks like the program has problem or the wiring right? i wan't to add i have done one ms 42 with no problems

Just curious, can you read fault codes through the 16pin OBD2 connector in the car with pins 14&18 Permanently spliced together on the 20pin round plug in engine bay? I hear most people leave those wires spliced together and have no issues?

hi pazzi just done all this to be able to switch off ews on a bmw i have just supercharged the flashtool says looking for cable and cant get it to work vagkkl 409.1 cable any help would be appreciated 🧐

Hi, can you help me? I have problem with download definitioo to my engine m52m20 with ms410DS3, I can't create accont on romraider, activation mail doesn't come. can You send definition file on mail? please :)

Can you use an ms41 in a ms40.1 m50 wiring loom?

can you tune with this or just make small changes to your ecu?

en kerennyt hirveesti vielä perehtyä mutta onko tuossa tullut vuosien myötä mitään ongelmia uusien tietokoneitten kanssa pitäiskö toimia ihan kaikilla windows versioilla

Hi Pazi, love the videos. I have the partial .bin file downloaded and am having trouble deleting ews in romraider. What should I change the decimal value in the 8th byte of control bits section? It is '30' stock, I've seen other say make it '22'. Will I ruin the ecu if I mess it up? Thanks so much, coming from the US!

hi there....i have a question please...my car was a e36 320i m50 and i swap the engine for a m52b28....everythink works good...my problem is i can not read anything when i put the plug for reading problems and codes....what can it be the problem...i have done a remap and the tuner had to make everything and see everythink only direct from the ecu pluged to hes computer because he could not come in from this obd plug ....

Hello for the socket 20 pin you have inverted pins 14 and 18 or you only connect the wire of pine 14 on pin 18 thanks

Great video as always, i should have seen this earlier! Is it possible to reach 350hp using ms41 1997 or it is better and easier to use a blanc ecu?

Hello pazi to increase the engine power it is necessary to increase base injection or wot enrichment or both thanks

I'm having trouble with my romraider account activation and I need the ms41 ecu definitions is there anyway you can email me the XML

yo tengo un bmw e46 328i 1999 por no puedo entender lo k disen

Is there any guides on how to convert a ms41.0 to a ms41.2?

Do you have to save it as bin? I was sent a remote tune and it wasn't a .bin file, and it worked when i uploaded it to my dme. I am editing the tune in romraider, and wondering if I need to ad .bin onto it for it to work?

Have you ever used MPPS? I’ve got a ms42 Dme and it reads and id’s the dme fine but I’m not sure if I want to hit the “write” button lol

I cant activate a romraider account and I need the ms41 ecu definitions is it possible to email me the XML file??

My 2000 z3 has obd2 port is inside cab in console on passengers side, what cable will I need for flashing.

try to modify my obd2, the same way you did yours, but ran to a problem. ... my obd2 is wired different. #14 has a black wire... #15 is green... #17 has a white wire with a blue jumper, that go's to #20 and #19 is red.... so my question is what do I need to do to make it work? Don't want to burn anything out lol.......

Very nice video . But the chipster Website is not working. What happened there ?

Nice information, thank you! Now i need to search somehow a map for m52b28 with m50 intake, anyone knows where i can find it?

Hey pazi i am a little Bit confused right now. I have a 1997 e36 with a ms41.0... I wired a obd cable to the ews exactly like on the romraider Forum. Now i just need the obd cable. In Germany we have kcan, kdcan, dcan and many many other types of cables. The one that you have in your description is 1. Only for cars after 2001 and 2. Not available in germany and if i search k-line cable in german ebay or Amazon i just get some weird adapter from round 20pin to obd and one more short obd to obd cable. I hope you Can give me some clearity about all the different cables Amy help me for what i have to go with. Greetings

will any obd2/usb adaptor work if i bridge the pins myself and have the 20 pin adaptor?

hi pazi!! i ve been looking to your videos and are awesome!! im looking for up the rev limiter and after doing everything you did, my m52 engine still on 6500. have i done something wrong?

I am trying to make my pre excisting m52b25 ecu run the stroked and tuned m52b28 thats under the bonnet now. My original plan was to. Partial read and partial flash my friends 528 ecu into mine but noticed that his was id 41 and mine id 59 so my ecu has much less maps available. Can i still do this or will it brick the shit

HI @pazi88 it is possible to tune with this ECU turbo engine? Or there is just no way to use turbo engine without KDFI? Thx for response! Like you videos!

Thank you!!!! Good soft!!!

I cant get the new quickflash software to work, the buttons is just grey, im using a galletto cable and obd adapter where pin14 and 18 is bridged. Any guesses on whats wrong?

I bought a cheap 1999 MS41.0 for testing, because my car (M52B28) is 95 and the ECU is not flashable. If I manage to disable the EWS, is it safe to change the ECUs? Like mileage differences or pinouts?

hi, i tried to register on romraider forum but they didn't send me activation email, can uhelp me somehow ? i would be thankfull for help

Do you have a secondary air pump and evap delete with the tune? I have us m52 swap and need to run obdii with m50 manifold . And want to pass inspection

hello. I have 5WK9 0322-R ecu. Can i tune this ecu like you? It hasn't "index xx". And what is the R? Thank you for your answer.

Do u need flash voltage to read the partial? I keep getting an error when trying to read it saying access denied by ecu