[Soul_Glo]

The throttle lag has not much to with the gearbox and much more to do with the DME.


A new software calibration was just released for this engine:
SIB 24 02 12
Subject:
N52T/N55 with 8HP45: Delay in Engine Response
Model
F25 with either N52T or N55 engines and 8HP45 transmission up to 1/16/2012
Situation
When slowing down to lower suburban road speeds and then reaccelerating, a delay in engine response may be experienced
Cause
Unfavorable EGS and DME software calibration
Correction
Program the vehicle using ISTA/P 2.46.0 or higher

[buckybadger]

Originally Posted by Broken_Gearbox

The throttle lag has not much to with the gearbox and much more to do with the DME.


A new software calibration was just released for this engine:
SIB 24 02 12
Subject:
N52T/N55 with 8HP45: Delay in Engine Response
Model
F25 with either N52T or N55 engines and 8HP45 transmission up to 1/16/2012
Situation
When slowing down to lower suburban road speeds and then reaccelerating, a delay in engine response may be experienced
Cause
Unfavorable EGS and DME software calibration
Correction
Program the vehicle using ISTA/P 2.46.0 or higher

Thanks, so this is only for F30's till 1/16/2012 production dates? My car was built in November 2013, so it should not be impacted, correct?

[Soul_Glo]

Originally Posted by mintoo

Thanks, so this is only for F30's till 1/16/2012 production dates? My car was built in November 2013, so it should not be impacted, correct?

The update was not widely publicised so the dealer will not do anything unless you mention that it is a problem. It can be addressed under warranty. The trouble is that cars still roll off the production line without this. The alternative is to adapt the throttle with a pedal box if you are out of warranty. That's all I know about that.

[buckybadger]

Originally Posted by Broken_Gearbox

The update was not widely publicised so the dealer will not do anything unless you mention that it is a problem. It can be addressed under warranty. The trouble is that cars still roll off the production line without this. The alternative is to adapt the throttle with a pedal box if you are out of warranty. That's all I know about that.

Thanks, I do plan to get the MPPK. In that case, the DME will anyway be re-programmed.

[Dan203]

Originally Posted by gpchamp

I experienced the same issues when I got my '15 428i GC. The problem is the programmed throttle response, especially in Comfort Mode. Initially I avoided the "mushiness" of the pedal by simply driving in Sport Mode. However, I didn't like the way the transmission kept hunting for lower gears in Sport Mode, which got old very quickly in stop-and-go traffic. After doing some research, I found the Remus Responder, which re-tunes the stock throttle map and gives it far quicker and sharper response.

Appears that the Remus Responder is basically the same thing as the Sprint Booster I bought. So far I'm happy with the Sprint Booster. It's made the issue a lot less noticeable. It's like driving in sport mode without the aggressive down shifting and gear holding.

[gpchamp]

Originally Posted by Dan203

Appears that the Remus Responder is basically the same thing as the Sprint Booster I bought. So far I'm happy with the Sprint Booster. It's made the issue a lot less noticeable. It's like driving in sport mode without the aggressive down shifting and gear holding.

Exactly!

[blakei]

I have this issue on my F30 328i M Sport N26 engine, both in Comfort and Sport. Does the SI B24 02 12 apply to the N26?

I also found this updated bulletin:
"This Service Information bulletin replaces SI B24 02 12 dated March 2012."
https://static.nhtsa.gov/odi/tsbs/20...52360-6188.pdf

Still only refers to the N55.

Anybody else with this experience on the N26 engine? Is the best solution still just to drive in Sport/+ mode? I'm considering a Dinan Sport Performance Tuner -- would it help?

[SteveinArizona]

I have noticed the same lag with loaners. I don't have that lag with my 330e so I have attributed that to the lnstant torque of the electric motor (which, btw, replaces the torque converter).

[omgthedonny]

I notice a slight lag too in my 340i automatic Iv only had sticks before so I thought this was normal behavior or the car slowly applying power so you don't just rip the tires (even in sport+) with all that power instantly coming on but I was not sure because my loaner 240i msport automatic had the same type of feel

Almost like the car thinks about it for a second then says "oh looking for this? Boom"

[LMK5]

I have a 2017 330i and I definitely notice delay in throttle response, but only when hitting the throttle when coasting or from a rolling start. The delay in throttle response is quite pronounced. I absolutely did not notice this behavior in my 2014 328i with N26 engine. Up until this time I had attributed the difference to the peak torque coming at higher RPM on the B46 vs. N26, but it seems from these posts that may not be the case.

Like another poster mentioned, I also feel that sport mode in the 2017 is less aggressive than the 2014. Not sure why BMW did that since they were definitely trying to make the "base" car more sporty by making sportline standard.

[fpm79w]

Same lag problem here with a 430i LCI (B48O).

It's something that's driving me crazy and forcing me to always drive in SPORT to try to minimize it.

[LMK5]

Originally Posted by fpm79w

Same lag problem here with a 430i LCI (B48O).

It's something that's driving me crazy and forcing me to always drive in SPORT to try to minimize it.

Tough to tell if it's turbo lag or slow decision-making by the AT, but when I'm on the freeway coasting behind a slow driver and need to make a quick pass the delay can be downright dangerous. I have learned to just floor it to execute the fastest downshift possible. Two or 3 clicks of the "-" paddle shifter will also do it, then hold down the "+" paddle to get back into "D."

[Moupe]

Just installed the Racechip XLR (throttle/pedal tuner)a few days ago and have no regrets. 2019 F31 with the B46/B48 here.

[Dan203]

Just traded in for a Tesla Model 3 Performance and 0 lag on that one.

[bimmer456]

There's no lag in sport plus with B58. Some lag with B46 but sport with stick to the left reduces lag.