E89 Z4 INOAS boost ceiling with MHD Question

[Osiris]

Hey guys, I am new here, looks like allot of valuable info is to be had in these forums.

I have a question that I have asked on other forums a while back, However I have never had an answer and I am hoping that the Z4 people out there on this forum can answer.

I know the E89 Z4 although N54 has no lpfp sensor and its been a pita to deal with in terms of tuning and trouble shooting. I have a warlboro 450 pump in my car. I will list my mods quick before I go on:

Stage 2 lpfp
brand new hpfp rev 3
bms oil cooler valve
High flow silicon inlets
mamba hybrid stage 1 turbos
Stock airbox with Mr 5 mod for extra flow
catless downpipes
full stainless exhaust catless ( I kept the stock back boxes)
large FMIC
JB4
MHD BEF
Methanol injection with JB4 FSB controller (CP injection for now)
stainless Charge pipe with HKS BOV
3.5 bar sensor with harness

That's all I can think of now.

Now onto my question:

While running MHD before acquiring a JB4, I ran all the MHD maps Stage 0 - Stage 2+ including Ethanol maps, While running these maps I seemed to have a boost ceiling of around 14psi, I would sometimes hit 16psi but it would be very brief and then it would taper down to almost stock boost instantly ( I was using stock turbos at the time), I tried everything and could never get my boost to go higher, it's almost as if the Z4 has a boost ceiling that MHD cannot surpass.

Now I installed a JB4 and was faced with the exact same problem, boost was identical, JB4 on its own with no BEF and with a BEF yielded the same results until I decided to try a different BEF file relating to a different ECU revision, The Z4 comes with the INAOS file which knows of the missing LPFP sensor so it does not throw an error for this.
I loaded the BEF file for the IJEOS ecu and BAM boost was where it needed to be, 18psi, 16psi and with methanol in map 3 I can reach what ever PSI I want by setting the additive, provided I have the right octane levels.

Now the problem here is that I was getting the LPFP sensor missing error because the IJEOS is for E92 335 and E90 335 as far as I know of which both have a LPFP sensor.

Does the INOAS ECU file have this supposed boost ceiling I am experiencing because It can't get a reading from the LPFP thus it is unable to raise the load request? This is my theory anyways.

Please can someone in the know explain this phenomenon to me regarding the Z4 and this lpfp sensor problem.

 

[NoQuarter]

The (missing) LPFP sensor has not been a problem for anyone that I am aware of nor I have ever heard anyone describe a boost ceiling in the INAOS.

So... not sure what the real issue for you is but I think you may be chasing the wrong "problem"

Welcome to the Forum!

 

[Osiris]

The (missing) LPFP sensor has not been a problem for anyone that I am aware of nor I have ever heard anyone describe a boost ceiling in the INAOS.

So... not sure what the real issue for you is but I think you may be chasing the wrong "problem"

Welcome to the Forum!

It's absolutely a problem for allot of people that I know with the E89 z4 N54 platform which is why it is recommended to use the IJEOS file for the back end flashes instead of the INAOS when using JB4.

I would be keen to see some logs of people with E89 running stock turbos running MHD without JB4 to see what boost target is. See the thing is I wasn't having a problem meeting boost target, my boost was on point, the problem is the "Target" is low. As soon as I switched to IJEOS file my target raised to the levels they should be associated with each map on the JB4.

I am in South Africa and I asked this same question to a few guys I know with tuned E89's running big power with upgraded turbos etc and they recommended the IJEOS BEF route as they too had the same issues as me with low boost levels. If I am not mistaken the info comes from N54tech.com

Unfortunately the E89 Z4 is not the most common car in the tuning world so most people just assume that because its an N54 its the same and all tuning would be the same, unfortunately that is not the case The missing LPFP sensor is definitely causing issues with tuning via off the shelf maps like MHD.

 

[fmorelli]

Welcome!

I have stock turbos right now, running 19psi on E85 without a hiccup, thanks to @BQTuning, who probably knows more about tuning the Z4 than most anyone. He does MHD tuning, and you might want to work with him on your tune if going the MHD route.

Filippo

 

[Osiris]

Welcome!

I have stock turbos right now, running 19psi on E85 without a hiccup, thanks to @BQTuning, who probably knows more about tuning the Z4 than most anyone. He does MHD tuning, and you might want to work with him on your tune if going the MHD route.

Filippo

Thanks for the replies guys. I'm not wanting an MHD tune. I am just trying to understand why there is a cap on boost with the Z4 if running an off the shelf map. I know that if you do a custom tune it can be fixed I want to understand what is being fixed and how.

I did hundreds of logs on MHD trying many many different things all the way back from 2017 when I bought the car, the problem is absolutely there.

Thanks for the tip on @BQTuning

 

[matreyia]

Thanks for the replies guys. I'm not wanting an MHD tune. I am just trying to understand why there is a cap on boost with the Z4 if running an off the shelf map. I know that if you do a custom tune it can be fixed I want to understand what is being fixed and how.

I did hundreds of logs on MHD trying many many different things all the way back from 2017 when I bought the car, the problem is absolutely there.

Thanks for the tip on @BQTuning

MHD has the M Boost module which allows you to go up to 36 psi. You have not tried this?

 

[Osiris]

MHD has the M Boost module which allows you to go up to 36 psi. You have not tried this?

I haven't tried that no. If I ever decide to go back to MHD I may give that a try however I have methanol injection which is why I am running JB4 as I would need a separate methanol controller if I use MHD.

Even with JB4 if I write the INAOS bef supplied by BMS I end up with a boost ceiling, The only way for me to get past this is to write IJEOS BEF. It's very strange indeed.

 

[doublespaces]

I haven't tried that no. If I ever decide to go back to MHD I may give that a try however I have methanol injection which is why I am running JB4 as I would need a separate methanol controller if I use MHD.

Even with JB4 if I write the INAOS bef supplied by BMS I end up with a boost ceiling, The only way for me to get past this is to write IJEOS BEF. It's very strange indeed.

Have you contacted BMS about this issue? @Terry@BMS and @Payam@BMS also pop in from time to time.

It sounds like you have a couple of problems but I wouldn't be able to give much advice on the JB4 related questions. Perhaps you should use the correct BEF for your vehicle, I suspect the necessary tables are defined or known by someone.

 

[Osiris]

I've tried the correct INAOS bef for my car and when I use that boost goes out the window I read a post about this very issue on n54 tech with another person with an E89 Z4 sitting with the same issue, Which is where I saw one of the suggestion of going IJEOS route which did work I just don't like that it works, I hate using the wrong ECU map for my car! The problem is most of the tuning world tune the 135/335 and the Z4 is very low on the list, so the free BEF maps are not catering for the Z4. I will make a post on N54Tech and see the outcome there as well.

 

[fmorelli]

I've tried the correct INAOS bef for my car and when I use that boost goes out the window I read a post about this very issue on n54 tech with another person with an E89 Z4 sitting with the same issue, Which is where I saw one of the suggestion of going IJEOS route which did work I just don't like that it works, I hate using the wrong ECU map for my car! The problem is most of the tuning world tune the 135/335 and the Z4 is very low on the list, so the free BEF maps are not catering for the Z4. I will make a post on N54Tech and see the outcome there as well.

Hopefully @Terry@BMS has a moment to reply here, if he can help. If you post elsewhere and discover what the issue is, would greatly appreciate your posting it back here. Best of luck!

Filippo

 

[doublespaces]

Perhaps @BQTuning can chime in. Or @trebila

 

[Osiris]

Ok guys I did some testing. I was very interested in trying a full MHD Stage 2+ flash with jb4 as a meth controller and logging device along with all the monitoring it provides etc.

So I was running JB4 + BEF using the IJEOS setup as explained before and everything is running fine and boost is great other than the lpfp sensor error that a friend of mine coded out of the bef files for me. So what I did was flash back to a INAOS BEF and then once that was done I flashed back to stock INAOS, Once flashed back to stock I then Flashed the stage 2+ MHD full map 91 oct.

Now here is where the kicker comes in: When I did the first write I chose the N20 3.5bar sensor option in the MHD options before writing the map and once that was done I set JB4 to menu option 4/4 then set the map to 3 and the meth additive to 0 and went for a drive, car felt horrible, everytime I tried to boost the bucked and hesitated and then threw an engine light. The errors related to the N20 sensor, car wasn't happy so I then disabled the N20 sensor option in JB4 since its activated in MHD so the two are obviously conflicting. Car then sort of behaved and I did a 3rd gear pull and it accelerated hard all the way up to 19psi and held it. Car felt strong. I switched the car off and back on and was faced with engine light and n20 sensor errors again.

So After discussing with a buddy we realized that JB4 wants to control boost solenoids etc and needs to have control over the N20 sensor, so I then flashed stage 2+ again but unchecked the N20 3.5bar sensor option in MHD and then enabled it in JB4 and then the car was happy, no errors, smooth driving and full meth flow HOWEVER! Boost wont go above 11psi!!!
Same problem as before with stage 2+ and INAOS map! It hits 15psi for a split second but doesn't even reflect in the logs as it immediately goes down to 11psi and tapers down at red line to 10psi


What I am thinking of doing next is disconnecting the white JB4 connector from the ECU and plugging the original ECU white connector back to the ECU which essentially takes away all boost control from the JB4 and makes it purely a meth controller and monitoring controller and then writing stage 2+ again but with N20 3.5bar sensor setting checked and see if the car boosts to 19psi again and if meth flows.
Will this also take away all safety features from the meth?

For the life of me I cannot understand this whole problem it makes absolutely no sense why this boost ceiling doesn't exist when I use IJEOS. Really hoping @Terry@BMS or @BQTuning can chime in and let me know what the story is here, I would really like to run the correct bin associated with my car.

 

[Terry@BMS]

Not sure what boost ceiling you're referring too and I don't see a log above. But the JB4 does the TMAP sensor conversion so the flash needs to be set for the factory TMAP sensor. If you flash for a 3.5bar TMAP sensor then sometimes MHD acts up and you have to uninstall MHD and start over for it to properly unselect it.

 

[Osiris]

Reporting back years later with my findings. I forgot about this thread actually.
Many things have changed on my car since this thread was created. Lots of upgrades and lots of tuning. Firstly I ditched the JB4 as the OTS maps don’t work correctly with my car period! this is a definite as I spent years tinkering to no avail. It’s either have INA0S with a boost ceiling or IJEOS with full boost but LPFP sensor errors and the car really doesn’t feel great to drive. Running the JB4 on my car made my car feel horrible in many ways I will list some of the reasons why now:

1: waste gate rattle, I literally installed brand new turbos with waste gate repair kit, drove the car everything was perfect, installed the JB4 again and bam waste gate rattle. Disconnect the JB4 and run the car stock or run a Mhd flash and waste gate rattle is gone. It’s not your usual waste gate rattle though “The one where if your car is idling and you rev it up, when you let off the accelerator it rattles, that’s the normal flapper is worn rattle” This is not the rattle I would get with JB4, I would get rattle when the car is under slight load driving slowly, as I accelerate between 2.5k - 3.5k rpm the waste gates would rattle. So damn annoying.

2: The car would lurch, something with the throttle response wasn’t right, take JB4 out and its smooth again, put back and if I am in a parking lot and I try edge forward gently the car would lurch. It was just all round finicky to drive, this probably wouldn’t irritate most people but I’m super OCD and like my car to feel as smooth as it did when it left the BMW factory.

3: map 4 safety for meth “not flowing” error when meth was absolutely flowing! I would see it in the logs. And if I purged it would spray. If I ran map 3 with a lower boost setting this wouldn’t happen but as soon as I went over 18psi I would get map 4 safety no meth flow error. Weirdest thing I ever experienced and was the final issue that made me get rid of the JB4 altogether.

4: This is a biggie, the gear shifts with JB4 are awful on the DCT, far too soft, I actually got a overheated error pop up twice running JB4. I also flashed to the z4 35is gearbox flash and that helped slightly but still the gearshifts for the power the car was making was not great. My theory on this is due to JB4 being a piggy back system the car thinks its boosting 8 -9psi so the line pressure doesn’t increase and so when you make anything over 300wkw the clutches start to slip and overheat. Running MHD or a custom flash I don’t have this issue as the tune is written with DCT in mind. You can feel a MASSIVE difference between running JB4 and MHD with regards to the gear shifts. This alone made me veer away from JB4 with my car. DCT is expensive when clutches need replacing. With my custom tune my gear shifts feel amazing and I have never had that gearbox overheat error come up since and its been since 2018! And I’m running way more power compared to then.


There were a bunch of other issues that I can’t think of right now as this was a long time ago but since then I have ditched JB4 and MHD OTS maps and have gone custom tune and its been amazing! The car feels as smooth as when its stock! Has insane power compared to anything I ever got out of the JB4 or MHD OTS maps. The logs are incredibly clean.
I run a standalone meth controller which I have been running since 2019 now and it hasn’t given me a days issue. The JB4 FSB controller was just endless issues. I know that if I had gone custom BEF with the JB4 allot of these issues could have been ironed out but allot would still remain like the rattle and probably the DCT slipping clutches which is a no go for me.

Mods done since then:
Stand-alone meth controller (Coolboost)
Charge pipe injection 2x 4.5cfm nozzles
Port methanol injection, 6x 2.5cfm nozzles.
I have installed a 7.5” race inter cooler Replaced 2 x injectors.
Replaced all injector decouplers and seals.
Replaced all coils with Delphi coils.
1 step colder plugs.
Fitted 14t Mamba hybrid turbos.
High flow silicon inlets.
New engine mounts.
Full exhaust
ISC coil overs

Car runs amazingly, I gave JB4 and MHD a solid chance and I mean years of trial and error and many many people tried to help me sort the issues I was having to no avail. We even tried swapping JB4 controller and FSB module with no success so that possibility was also ruled out.

I have had quite a few people with E89 Z4 35i contact me during this time experiencing the exact same issues and I just told them all to run then IJEOS OTS maps and that worked for them as it did for me but its not the correct way of doing things. They also had all the same issues as me. I guess its just one of those things unfortunately.

I will make a thread soon of all the progress and stuff I have done to my car. It’s been a journey that’s for sure.

 

[doublespaces]

Yeah, some photos of your car would help with some perspective, glad to see you back.

 

[Osiris]

Yeah, some photos of your car would help with some perspective, glad to see you back.

My build thread

There we go, I ported my build thread over from BMWFanatics to spool street where you can see from the day I got the car to where it is now, this excludes the turbo build thread which I will tackle tomorrow

 

[General.Massacre]

As @Osiris said, alot has been done to the car over the years.

I can add however the following. The ROM that is on his [VIN]_original.bin file shows as IKC0S, not INA0S, we noticed this after some research, and got hold of the INA0S xdf "New Tables" xdf which had the VIN tables on.
The [VIN]_original.bin file never matched up to the INA0S xdfs, specifically when investigating Timing (Main) table and others. so the car ran on MHD stg2+ etc, but i think the ROMs tables were very similar, but some factors just didnt match up enough.
Thinking back, and also taking into account my numerous private discussions with @carabuser about ROMs, etc and how MHD works in the background when building the OTS maps, i can understand.

Things only corrected after some time ago when i converted and setup the actual Z4 35is INA0S ROM on Osiris car, and noted the Current HW ZB# change. and since then the only big thing done software wqise was a custom tune, to where the car is now (which is no slouch).

Since loading the 35is INA0S software the car was never tested again with the MHD OTS maps as we didnt have the need to due to the custom tune that was started shortly after loading the car.

I think, if we knew what know now about how software works, back then, we probably would have had more success with the JB4/BEF route and INA0S and actually had the car running correctly.
However at this point we just wont know, unless there is someone on this group tat is in a similar position driving a Z4 35i, not 35is.

Thought id give my 2c of input since all thats been learned over the years and whats been done.

 

[Osiris]

As @Osiris said, alot has been done to the car over the years.

I can add however the following. The ROM that is on his [VIN]_original.bin file shows as IKC0S, not INA0S, we noticed this after some research, and got hold of the INA0S xdf "New Tables" xdf which had the VIN tables on.
The [VIN]_original.bin file never matched up to the INA0S xdfs, specifically when investigating Timing (Main) table and others. so the car ran on MHD stg2+ etc, but i think the ROMs tables were very similar, but some factors just didnt match up enough.
Thinking back, and also taking into account my numerous private discussions with @carabuser about ROMs, etc and how MHD works in the background when building the OTS maps, i can understand.

Things only corrected after some time ago when i converted and setup the actual Z4 35is INA0S ROM on Osiris car, and noted the Current HW ZB# change. and since then the only big thing done software wqise was a custom tune, to where the car is now (which is no slouch).

Since loading the 35is INA0S software the car was never tested again with the MHD OTS maps as we didnt have the need to due to the custom tune that was started shortly after loading the car.

I think, if we knew what know now about how software works, back then, we probably would have had more success with the JB4/BEF route and INA0S and actually had the car running correctly.
However at this point we just wont know, unless there is someone on this group tat is in a similar position driving a Z4 35i, not 35is.

Thought id give my 2c of input since all thats been learned over the years and whats been done.

Fair enough but my suspicion is that the z435is file we have written to the car is still just a custom flash written to the ECU via MHD, When we write stage 2+ I suspect it will just wipe that and behave as if the car was back to stock again. we will need to give it a test sometime though and see what the outcome is. Would be interesting to see.

 

[General.Massacre]

Thats correct, the MHD OTS maps do overwrite any custom tunes...
But....

the 35is software we wrote on your car as a custom flash, was just to change the Current HW ZB# (8652514) i think is the number you on now.
So if you had to test and flash back to stock, or even MHD Map 0, im 100% positive it will be the Correct stock file created from the ZB#.

MHD uses this number, not the VIN number, to create the new file. this i figured out when trying various files on my car (335i) to ge tthe INA0S version correct. which @carabuser assisted with.

This is why flashing Stock feature on MHD didnt work on the 335i due to the ZB# being for a Z4, even though my VIN was 335i.

So, in all honesty, for any Z4 35i owners having this Boost Ceiling issue with a BEF or MHD OTS map, i am very sure its due to the ROM being IKC0S, not INA0S as we initially thought by assumption.

 

[carabuser]

First I've heard of any issues with the Z4 boosting on any ROM. Certainly not a common issue as I've worked on a few Z4s and they usually boost better than the 335i.

I've had a custom tune on my Z4 for the last 7 years. It originally came with IGD0S, I then updated to IMC0S and had to re-tune again and finally INA0S came out around 2013 and that needed a new XDF building a map working out for that too. Never once has an issue with boost being limited.