[TheClaw]

Hello all, I have a 16' M235i 8-speed auto, with about 60K miles. I recently went from a BMS stage 1 plug and play, to Bootmod3 Stage 2, and installed a ARM FMIC as well.

I have noticed this problem prior to this to an extent, but now it is becoming extremely frustrating. Some pulls I do, I feel 100% of the power and torque and that "turbo-pull" feeling when it kicks in. Other pulls, it feels like the car has lost 200hp and does not pull at all, and it feels as though something is being held back. I have no check engine light, and I even re-flashed everything to ensure it was properly done.

I have also always had a ton of throttle delay with this car, to the point where I will have to use paddles to downshift in almost every scenario, but now it's to the point where sometimes I don't even feel safe with how late the power comes on after I have pushed down the accelerator. I was also recently involved in a small accident to the front bumper, however I do not believe there to be any damage to any internal parts, and it was minor paint damage. Any help would be very helpful!

(As a side note, I am also running winter tires right now, and it is starting to warm up beyond the recommended temperature for them, however I do not think this is the problem, I am unsure about how the XDrive could limit power with loss of traction.)

[XutvJet]

What drive mode are you using when this happens?

What octane are you running and which octane map?

[TheClaw]

It occurs in both Comfort and both Sport modes, however it's more noticeable when I am in Sport and Sport+. I have run Stage 2 93 Octane as well as Stage 2 AGG 93 Octane and the problem persists with both of them.

[JMcLellan]

What are you seeing in the logs? Curious what the throttle % looks like, any timing corrections, etc.

Any chance this could be a random boost leak?

[Ajowhan]

Did you check for code?

If you suddenly lose a lot of power. Could be maybe fuel pressure is off? hpfp.. That should cause a code though even a engine malfunction warning.

Hard to say what cause it without more information

[TheClaw]

I'm not sure how to use the log feature yet, I'll try and figure that out and get back to the thread. I checked for codes yesterday and nothing was showing.

[JMcLellan]

Originally Posted by TheClaw

I'm not sure how to use the log feature yet, I'll try and figure that out and get back to the thread. I checked for codes yesterday and nothing was showing.

Good call. I recommend log reviews whenever you change tunes, adjust fuel mixes, or when adding /removing mods. Very insightful and there is a community that will review and provide feedback.

[TheClaw]

Ok, I'm going to log today and post it here. Just to be sure, I an doing 4th gear pulls from 2500 to 6500 RPM?

[JMcLellan]

Originally Posted by TheClaw

Ok, I'm going to log today and post it here. Just to be sure, I an doing 4th gear pulls from 2500 to 6500 RPM?

I try to stick with 3rd gear so I don't go too fast but yes seeing data from 2K up to 6500 or even redline is preferred. I haven't read BM3 logs before as I'm MHD but I'm sure someone else can chime in.

[TheClaw]

I logged three runs from 2.5k RPM to Redline around 7k RPM while I was in 3rd gear. I have linked all three below! If anyone knows how to read these please help!

https://www.bootmod3.net/log?id=642c...90c6b9bf64aacc
https://www.bootmod3.net/log?id=642c...729b286ce7e6d3
https://www.bootmod3.net/log?id=642c...0b43981b6b86f9

[MLJR235]

Originally Posted by TheClaw

I logged three runs from 2.5k RPM to Redline around 7k RPM while I was in 3rd gear. I have linked all three below! If anyone knows how to read these please help!

https://www.bootmod3.net/log?id=642c...90c6b9bf64aacc
https://www.bootmod3.net/log?id=642c...729b286ce7e6d3
https://www.bootmod3.net/log?id=642c...0b43981b6b86f9

Seems like you're building up too much boost over target starting right at 3500 rpm. Your boost target is set at about 17psi and you are upwards of 18+psi in some places.

Simultaneously, and I assume as a result of this, your Throttle Angle goes from 100% down to near 40% to bring you to or below target boost values.

Not sure why you're building up more boost than target ?? Someone more experienced can probably guide you further on the issue.

The throttle cut is most likely what you are feeling during your pulls.

[TheClaw]

I also found that to be interesting, from other datalogs I've seen there is almost always around a 1 psi difference between target and actual, and it's always less rather than more. I don't entirely understand what throttle angle means, as I keep my foot down the whole time, but that drop feels indicative of what I actually feel in the car... A sudden loss of throttle followed by a huge boost of power, like a delay.

[MLJR235]

I would run this by BM3 to see what they suggest you do. Not sure if a fix is as simple as raising the target boost ceiling in the tune or have you do troubleshooting on your end... Wish I was of more help.

[mecheng77]

Go to stock, you will never have a problem.

[AmuroRay]

I’ll look in a bit, I’d also recommend resetting throttle adaptions

[TheClaw]

I've reset throttle adaptations and I'm contacting BM3. It's becoming more apparent that's it not really a loss of power, but moreso such a significant delay with the throttle that it just feels slower until the power punches in hard.