Tuning questions please help me

[JCampbell_Soup]

Has anyone been able to tune/code the MS45.0 to disable the post cat oxygen sensor?

I have an M54B25 with primary cats removed. I have been living with the check engine light for almost a year now but it is time to fix this issue permanently so i can i know if other issues pop up.

Everyone seems to be able to tune the MS43 fine, seems there are plenty of cheap flash tunes floating around but when it comes to the MS45.0 the cost to preform tunes skyrockets.

Any help would be appreciated

[JCampbell_Soup]

So the ms45.0 is off the table completely?

[Steeler]

The market for the tuning of the ECU in the non M Z4 is very small. So tuners do not waste their time
There are options out there but again it is hit and miss if you get response.

[JCampbell_Soup]

It is weird because later model e46’s use the same ecu. It is possible to downgrade to ms43 which is more widely used and is tuneable so perhaps i will have to go down that avenue.

[RevsPlease]

I find myself in the same unfortunate situation at the moment. There are very few folks out there that are capable of live dyno-tuning the MS45 DME, so if you are looking to get a custom map made locally specifically for your vehicle you will likely not have any luck.

That being said, there ARE tunes available to do what you're asking for.
Epic Motorsports can write a custom map, including rear 02 delete, for you to remotely upload:

https://epicmotorsports.com/ecu-tune...es-z4-e85.html

ESS also does a tune for this DME with the option for custom requests:
http://esstuning.com/ms45-m54b30-ecu-tuning-software/

Active Autowerke too:
https://store.activeautowerke.com/co...re-3-0-2003-05

I haven't gone done any of those avenues yet but as I understand it, BMW left little to be had by way of tuning the software for the M54 so gains are pretty minimal.

[Azeka1]

Try giving Jordan a ring over at RK Tunes. I just used them for my Z4M Coupe and they did a nice job for a better price than anyone else (I paid $500 with O2/EGT delete and included shipping to/from for the bench flash). They are getting quite popular here in the NY/NJ area.

https://www.rktunes.com/collections/e46

If what you say about the ECU being the same as the e46, he should be able to help you out. Their site says $450 for 99-06 e46.

[vbelsky]

I'm gonna just convert mine to MS43. It's all plug and play.

[Taskmaster]

There are plenty of tuning options -

Epic
BPC
AA

[Westersund]

I'm sure my tuning guy can make that happen, he did it on my Z3 Coupe. He's a genuis. But he's located in Sweden so that would require you to send the ECU. Maybe there's a option that's closer geographically.

[pokeybritches]

Originally Posted by RevsPlease

I find myself in the same unfortunate situation at the moment. There are very few folks out there that are capable of live dyno-tuning the MS45 DME, so if you are looking to get a custom map made locally specifically for your vehicle you will likely not have any luck.

That being said, there ARE tunes available to do what you're asking for.
Epic Motorsports can write a custom map, including rear 02 delete, for you to remotely upload:

https://epicmotorsports.com/ecu-tune...es-z4-e85.html

ESS also does a tune for this DME with the option for custom requests:
http://esstuning.com/ms45-m54b30-ecu-tuning-software/

Active Autowerke too:
https://store.activeautowerke.com/co...re-3-0-2003-05

I haven't gone done any of those avenues yet but as I understand it, BMW left little to be had by way of tuning the software for the M54 so gains are pretty minimal.

This is a pretty well-read response, but I'd like to clarify a few points.

1. Unfortunately, only standalone ECU's can be live tuned on the dyno. OEM ECU's typically cannot be live tuned... only reflashed. That's where the problem lies for us.

A standalone ECU allows the tuner to adjust the tune in real time, while the car is running on the dyno, and see an immediate change. This is "live tuning". OEM ECU's require the car to be shut down, a new tune flashed in, and then the car is tested again on the dyno to measure the results. Reflashing is trial and error. Ultimately, there will be a trade-off between time spent on the tune versus quality of the tune. A good tuner can use his experience in knowing what historically has worked, in order to significantly reduce time spent on the dyno... but even the best tuners will only get the tune "close" with a reflash.

2. The Z4 ECU takes over an hour to read/write, so the car will need to sit idle on the dyno for an hour+ every time the tune is reflashed. This gives the tuner 6 (or less) reflashes if the dyno is rented out / tied up for a full day. It only takes a few minutes to reflash the software on most other cars, so the Z4 platform represents a huge cost investment for a low volume vehicle.

3. Definition files for the Z4 are hard to come by.

Tuners usually purchase a definition file for the vehicle which they are tuning. The definition file is essentially the mapping of the ECU. Definition files are used by the tuner's software suite to enable the tuner to adjust fuel and compensation tables, injector data, torque limiters, spark advance, etc. Software developers create the definition file (identify where the fuel/ignition maps are located in the ECU), and tuners tweak the values.

The more popular the vehicle, the more complete the definition file. It's not uncommon to be given a definition file for a low volume vehicle with mislabeled tables and missing data. For example, if your tuning software can't remove the torque limiter, then the car will go into limp mode every time the artificial airflow limits are exceeded. Certain parts of the definition file are absolutely required, and without them a proper tune cannot be completed.

If the definition file for a vehicle doesn't exist, the tuner will have to make it himself with a tool like Winols. The raw hex data on the ECU is read out by the program, and the tuner looks for patterns and shapes in the data. Data that looks like a sawtooth wave may be fuel tables vs load, ignition timing vs rpm, or temperature compensation tables (and so on). Torque limiters have tables of values that increase slowly and then decrease again. It takes a lot of experience or a lot of trial and error (time) to figure out which tables are which. Rumor has it that there are hundreds or even thousands of tables in the MS45.0 ECU.

******

Ultimately, there's nothing special about the MS45.0 ECU. There are a lot of obstacles in terms of the read/write time and lack of definition file support, and with the low volume of tunes that could be sold, it's difficult to make a business case for development. Nevermind that for a home tuner, you'll need to rent dyno time and spend $10k on tools like K-TAG, KESSv2, and Winols.

[Steeler]

Very informative Josh.