f15 X5 50i power delivery with BMS...

[ellisina4]

I own f10 2015 550xi (July 2015 production date) and my wife has f15 2015 x5 50 (September 2014 production date). Has anyone notices that, despite a very smooth power delivery, when you press the gas pedal from the dead stop, on X5 it is feels like the car jerks a little? This is complete opposite from my 550xi where it is smooth as I can possibly wish for.

When I installed BMS chip (12 oÂ’clock setting) into X5, this initial jerkiness became more pronounced. Also, when the temperature outside got a little cooler (60Â’s) and when we drive off in the morning, first few minutes the car stumbles from dead stop, almost like it will die (this was not happening without a tune).

When I installed the BMS chip into my 550, there are no issues whatsoever.
Has anyone experiences anything like that with or without tune?
Thank you

[RM707]

Wow, I have exactly the same issues on my 15 X5 50i with BMS tune. So you are not alone.

[BayX5]

This is one of the main reasons I'm debating spending the extra money for the Dinan. We had a e70 50i and my wife thinks our f15 stock is a lot more sensitive throttle wize. She describes it as jumpy. We've had cars chipped in the past that were like this and it made it worse.

[Bigb348]

I feel that in sport mode, which I use 90%+ of the time, that there seems to be a throttle delay. When in sport + mode, I feel power seems more immediate but the shifts aren't as pronounced.
I am awaiting my Bms tune, and hope it doesn't worsen throttle response and/or cause a stumble upon cold start.

[Alan l.]

I think the slight throttle response is normal from the N63TU. I noticed the same thing on my 550 and also on a 650GC loaner I had. It was the first thing I noticed when compared to my previous 535. The N55 while isn't nearly as powerful has instant throttle response (especially with MPPK).

[onfireX5]

My 2016 50 has the same throttle delay in comfort mode pure stock no tune. Sport plus stops the delay.

Added BMS and it did not help or hurt the delay. Feels stock. Present in comfort, gone in S+.

[ellisina4]

Originally Posted by BayX5

This is one of the main reasons I'm debating spending the extra money for the Dinan. We had a e70 50i and my wife thinks our f15 stock is a lot more sensitive throttle wize. She describes it as jumpy. We've had cars chipped in the past that were like this and it made it worse.

This is funny, my wife uses the same jumpy nomenclature. I understand that these are different cars, extra 1000lb to compensate... At the same time, it is strange to me that 550 is smooth and x5 50i is jumpy, even though engines and transmissions are the same.

I wonder if it is the DME software update as mine is 2015 model with 2014 build date. I will ping x5onfire who has 2016 model to chime in. He has been using BMS tune also.

[onfireX5]

Wife's N55 is much smoother part throttle.

[ellisina4]

Originally Posted by RM707

Wow, I have exactly the same issues on my 15 X5 50i with BMS tune. So you are not alone.

Are you stock or tuned?

[ellisina4]

The following is the response I received from BMS:

"The Stage1 tune is just going to magnify the stock tuning a few PSI.
So whatever problems exist with the factory tuning on the vehicle will still be there with the Stage1. There isn't much we can do for you on
either issue you're having."

Just an FYI.

[RM707]

Originally Posted by ellisina4

Are you stock or tuned?

It's stock 50i with BMS. And I completely agree with the fact that it's not tune that causes this issue. To confirm it I uninstalled tune this morning and issues with "cold start engine bogging" still persist. Need to see dealer I guess.

BTW, I can recommend tune to anybody. It takes 2 minutes to install (30 seconds uninstall). And you definitely can feel extra torque.

[ellisina4]

Originally Posted by RM707

It's stock 50i with BMS. And I completely agree with the fact that it's not tune that causes this issue. To confirm it I uninstalled tune this morning and issues with "cold start engine bogging" still persist. Need to see dealer I guess.

BTW, I can recommend tune to anybody. It takes 2 minutes to install (30 seconds uninstall). And you definitely can feel extra torque.

I may not have been very clear in my original post, but the "cold start engine bogging" was not present with Stock tune, it only appeared with BMS. When I took off BMS, bogging disappeared, but after a few days. Do not rush to the dealer.

The hesitation from dead stop was the one that got worse with the tune.

[RM707]

Originally Posted by ellisina4

I may not have been very clear in my original post, but the "cold start engine bogging" was not present with Stock tune, it only appeared with BMS. When I took off BMS, bogging disappeared, but after a few days. Do not rush to the dealer.

The hesitation from dead stop was the one that got worse with the tune.

Hmm, I guess we have different issues then. In my case I have zero hesitation. With tune it's actually almost instant launch (too much power ).

[twelve535i]

Originally Posted by ellisina4

The following is the response I received from BMS:

"The Stage1 tune is just going to magnify the stock tuning a few PSI.
So whatever problems exist with the factory tuning on the vehicle will
still be there with the Stage1. There isn't much we can do for you on
either issue you're having."

Just an FYI.

Does this mean that your stock issues will still be present or the tune will magnify you issues?

[ellisina4]

Originally Posted by twelve535i

Does this mean that your stock issues will still be present or the tune will magnify you issues?

From the BMS reply, What it sounds to me that both will happen: stock issues will be present and tune will make these issues more obvious. Again, in my case, the "cold start engine bogging" appear only with the tune. It is possible that bogging were not as obvious without a tune.
On the other hand, I will call my stealership and check if there are any DME updates available for my VIN.

[X5Jouster]

Originally Posted by ellisina4

When I installed BMS chip (12 oÂ’clock setting) into X5, this initial jerkiness became more pronounced. Also, when the temperature outside got a little cooler (60Â’s) and when we drive off in the morning, first few minutes the car stumbles from dead stop, almost like it will die (this was not happening without a tune).

on a cold start, with or without the tune. My X5 50i has the same problem. it jumps around like jackrabbit with initial throttle and until its remotely warm.

[r33_RGSport]

Edit: Disregard, just remember different air filter setup on the F15/F16.

[RM707]

I still don't think it's BMS tune. I've had tune since May and my car was perfect (no bogging/choking). It developed this habit last month. My guess it has something to do with cold weather/car problem(existing). Tune just can not go bad. It works right now and works perfectly. Those 500+ lb/ft of torque feeeeeeels very good.

[X5Jouster]

Originally Posted by RM707

I still don't think it's BMS tune. I've had tune since May and my car was perfect (no bogging/choking). It developed this habit last month. My guess it has something to do with cold weather/car problem(existing). Tune just can not go bad. It works right now and works perfectly. Those 500+ lb/ft of torque feeeeeeels very good.

its feels like lean fueling, but i wholeheartedly agree about those 500 foot pounds

[Bigb348]

Bms tune installed today. Had a few launches, and boy what pinned to the seat torque w the power of that monster under the hood. Will give it some time and report back.

[r33_RGSport]

@Bigb348 that must have been fun.

[bjcarls]

Originally Posted by X5Jouster

on a cold start, with or without the tune. My X5 50i has the same problem. it jumps around like jackrabbit with initial throttle and until its remotely warm.

My e70 did/does this, nothing to do with a BMS. Agree