My M4 GTS continues to accelerate after I let my foot off the gas

aBMWfan · 04-14-2018, 09:50 PM

Quote:

Originally Posted by delfunk

Bem4 please make sure you have them put it on the repair order so there is a record. BMW needs to know of these issues.

Will do

delfunk · 04-15-2018, 09:35 AM

I just learned about Valvetronic. I guess I am behind on the times. BMW claims the intake valves close in .3 of a second. There is a throttle body as a fail safe. So why is the car still accelerating for 2-3 seconds? Thanks for filling me in gingerbread

This is a serious concern and it appears that this might be happening on more than a few cars. Of course no codes get stored when this happens. I'm sure this is what they will tell Bem4 as well.

BMW9 · 04-16-2018, 12:43 AM

Quote:

Originally Posted by delfunk

Has anyone experienced the car still accelerating once you let your foot off the gas for a couple of seconds under full acceleration? Another GTS owner has verified this with me as well. There are no fault codes and of course and they cant duplicate it. It's always when driving hard from 1-2 gear.

I'm thinking the water injection system is still shooting water and is malfunctioning or a faulty throttle body.

The BMW engineer thinks it's the turbos still spooling and air is getting into the intake. I told him impossible there is a throttle body and a blow off valve. He didn't like hearing that. Maybe the throttle body has an issue?

This has happened to me several times in two different cars, but not in any BMWs that I have had. It always happens right after lifting off from an aggressive throttle application and it's right before taking a turn. Throttle does not stay open fully but there is enough acceleration to scare the crap out of you even though you are not on the gas. I don't think water injection has anything to do with it (it happened in my C63 and my Gallardo). Despite reporting it to the dealers, No one could explain or remedy the problem for me. The floor mats were of course ruled out as the cause of the problem but that also has happened to me during full throttle acceleration. Thank god it happened in my 280 ZX which only had 180 hp.

Day Laborer · 04-16-2018, 08:50 AM

Maybe take some WD-40 and clean under your accelerator pedal?
Could be some dirt or gunk that might be making the pedal sticky?
Just a thought

delfunk · 04-16-2018, 10:48 AM

This has only happened to me while driving straight thankfully. I will examine the throttle pedal but I believe the dealer has already done that.

I will take it in again and have BMW look into the valvetronic issues.

aBMWfan · 04-16-2018, 06:42 PM

Quote:

Originally Posted by delfunk

This has only happened to me while driving straight thankfully. I will examine the throttle pedal but I believe the dealer has already done that.

I will take it in again and have BMW look into the valvetronic issues.

In my case, it happened after giving it some gas around a turn, and the car was straightened after the turn,

My dealer appt. got pushed to Wed. I’ll be sure to ask about it

delfunk · 04-24-2018, 10:56 AM

After taking the car in four times for this BMW finally agreed to reprogram my computer. Here is what the service rep said:

"Your concern was that the Valvetronic did not function properly. We did not find any relevant faults stored. We contacted BMW, as per their request we performed programming and complete encoding. Initialized windows. Perform valvetronic test plans and ran without faults. Vehicle is operating to specs."

Bem4 maybe they can do this for you? Might help.

AlpineWhite_F80 · 04-26-2018, 07:43 AM

It has happened to me around 2 times in the past 1 1/2 years, and only after hard acceleration then letting go, the car just kept going for a couple seconds. I drive a F80 ZCP

CanAutM3 · 04-26-2018, 07:44 AM

Quote:

Originally Posted by delfunk

I just learned about Valvetronic. I guess I am behind on the times... ...Thanks for filling me in gingerbread

I had already told you so in post #6

your own thread that is

Quote:

Originally Posted by delfunk

BMW claims the intake valves close in .3 of a second.

According to the video, that was back in 2001. In those days, BMW ///M assessed that this type of response was not sharp enough for the sporty characteristics of an "S" ///M engine, hence why the S54, S85 and S65 still had individual port throttle bodies. However, with the S63 and S55, the Valvetronic technology had evolved sufficiently for ///M to use it in their engines. I have to assume that modern Valvetronic has a much faster response than the 0.3 seconds referred to in the video.

CanAutM3 · 04-26-2018, 08:57 AM

Quote:

Originally Posted by gingerbread

Is this with DSC on ? Does it feel like continued acceleration or no engine braking ? Ive read somewhere in the training documents that is the DSC can adjust the level of engine braking based of many factors. It does this to not unsettle the rear end of the car with excessive engine braking. Some factors are rain, outside temps, cold tires and so on. Maybe some more info on what is happening environmentally, road conditions, are you turning, etc.

Are you sure what you have read relates to the DSC holding engine power? Because IMO that could be very dangerous where the engine continues to provide power even when the driver lifts off. I seriously doubt they would design DSC that way.

Maybe you are confusing from your readings the DSC interaction with the DCT and e-Diff, where the DSC can command the DCT to open both clutches and/or the e-diff to lock/unlock on decel when slip is detected.

Raul1428 · 06-06-2018, 03:54 AM

Any updates on this? Im having the same issue on my 2015 m3. When i go from 100% throttle in 2nd and shift to 3rd and let go of the gas pedal, it continues to accelerate at around 3k-4k rpm, I have to mash the brake for it to stop accelerating. My car is completely stock and it happens in Sport+ with MDM. Also have noticed it happen when im in traffic and trying to do short pulls.

I managed to record the incident on my go pro with M lap timer

aBMWfan · 06-08-2018, 12:37 PM

Quote:

Originally Posted by Raul1428

Any updates on this? Im having the same issue on my 2015 m3. When i go from 100% throttle in 2nd and shift to 3rd and let go of the gas pedal, it continues to accelerate at around 3k-4k rpm, I have to mash the brake for it to stop accelerating. My car is completely stock and it happens in Sport+ with MDM. Also have noticed it happen when im in traffic and trying to do short pulls.

I managed to record the incident on my go pro with M lap timer

My dealer didn’t say anything when I brought it up.

You seem to have documented your issue well. Let us know how it goes when you mention this.

BMW9 · 06-10-2018, 04:49 AM

could be a problem with the throttle Controll module.

delfunk · 08-28-2018, 12:33 AM

Quote:

Originally Posted by Raul1428

Any updates on this? Im having the same issue on my 2015 m3. When i go from 100% throttle in 2nd and shift to 3rd and let go of the gas pedal, it continues to accelerate at around 3k-4k rpm, I have to mash the brake for it to stop accelerating. My car is completely stock and it happens in Sport+ with MDM. Also have noticed it happen when im in traffic and trying to do short pulls.

I managed to record the incident on my go pro with M lap timer

That's great you recorded it. What did the dealer say?

They can't duplicate it and they tell me there are no relevant fault codes although the ZGM module failed to sync several times.

delfunk · 10-08-2018, 02:06 PM

Quote:

Originally Posted by Darth One

Haven't had that issue but I do have to say that the throttle is the worst thing about this car. BMW really fucked it up.

That said, it's kind of the same thing as the mole on Cindy Crawford's face

I wrote the NHTSA and they told me I am the only one to complain about this and more need to step up. Whoever is on the please go to the wendiste and file a complaint. It takes five minutes. They need your vin and a few other pieces of information.

Nhtsa.gov

delfunk · 02-20-2019, 10:13 PM

I had fault codes pop up that stated the accelerator angle was incorrect and BMW said it was normal!

Schultz28 · 09-26-2020, 12:07 AM

Quote:

Originally Posted by Raul1428

Any updates on this? Im having the same issue on my 2015 m3. When i go from 100% throttle in 2nd and shift to 3rd and let go of the gas pedal, it continues to accelerate at around 3k-4k rpm, I have to mash the brake for it to stop accelerating. My car is completely stock and it happens in Sport+ with MDM. Also have noticed it happen when im in traffic and trying to do short pulls.

I managed to record the incident on my go pro with M lap timer

Just had the same exact thing happen to me for the first time. Full throttle in 2nd then shift into third for a short pull....

Let off the throttle and expected to decelerate but the car kept increasing in speed for about 1-2 seconds before I got on the brakes in reaction to the increasing speed which seems to have canceled the acceleration.

Luckily there were no cars around. But that’s a terrifying issue to have. Really hope to not experience it again.

Has anybody been able to find the actual cause of this?

erictrainer · 09-26-2020, 07:48 AM

Quote:

Originally Posted by Darth One

Haven't had that issue but I do have to say that the throttle is the worst thing about this car. BMW really fucked it up.

That said, it's kind of the same thing as the mole on Cindy Crawford's face

Since no one ever said anything I thought that mole only bothered me

Sorry didn't mean to go off topic

FormulaMMM · 09-26-2020, 08:14 AM

Quote:

Originally Posted by Schultz28

Just had the same exact thing happen to me for the first time. Full throttle in 2nd then shift into third for a short pull....

Let off the throttle and expected to decelerate but the car kept increasing in speed for about 1-2 seconds before I got on the brakes in reaction to the increasing speed which seems to have canceled the acceleration.

Luckily there were no cars around. But that’s a terrifying issue to have. Really hope to not experience it again.

Has anybody been able to find the actual cause of this?

What throttle setting?

Schultz28 · 09-26-2020, 10:49 AM

Quote:

Originally Posted by FormulaMMM

What throttle setting?

Sport plus.

FormulaMMM · 09-26-2020, 11:47 AM

Quote:

Originally Posted by Schultz28

Sport plus.

Reluctant to question someone's lived experiences, but have to wonder if F8X sport plus throttle setting and this issue are coincidence.

There is no deadzone at the top of the throttle in this setting, it is effectively on/off.

I would find an empty road, do the 2nd to 3rd gear pull you detail 10x. Make sure with each one you're fully off the throttle -- as in, snap your foot off the gas like it's on fire.

if you aren't able to replicate the issue, then you might consider "user error" being a potential cause of the prior experience. Again, where user error would be as small as continued slight pressure on the gas when you thought you were fully off.

White340 · 09-26-2020, 11:57 AM

Can you post a video of this?

04-15-2018, 09:35 AM	#24
delfunk Private First Class 32 Rep 110 Posts Drives: 2016 M4 GTS Join Date: Apr 2018 Location: Sacramento, CA iTrader: (0)	I just learned about Valvetronic. I guess I am behind on the times. BMW claims the intake valves close in .3 of a second. There is a throttle body as a fail safe. So why is the car still accelerating for 2-3 seconds? Thanks for filling me in gingerbread This is a serious concern and it appears that this might be happening on more than a few cars. Of course no codes get stored when this happens. I'm sure this is what they will tell Bem4 as well. Last edited by delfunk; 04-16-2018 at 10:47 AM..
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04-16-2018, 08:50 AM	#26
Day Laborer Lieutenant Colonel 1746 Rep 1,889 Posts Drives: M5 CS / iX 50i Join Date: Dec 2009 Location: NY, NY, CT, PA, MD, VA, DE, FL iTrader: (11) Garage List [0.00]	Maybe take some WD-40 and clean under your accelerator pedal? Could be some dirt or gunk that might be making the pedal sticky? Just a thought __________________ https://www.instagram.com/day_laborer/ *(DM me from this account)* Email: nextlevelautobrokersdc@gmail.com Part-time with Next Level Auto Brokers, LLC https://www.instagram.com/nextlevelautobrokers/
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04-16-2018, 10:48 AM	#27
delfunk Private First Class 32 Rep 110 Posts Drives: 2016 M4 GTS Join Date: Apr 2018 Location: Sacramento, CA iTrader: (0)	This has only happened to me while driving straight thankfully. I will examine the throttle pedal but I believe the dealer has already done that. I will take it in again and have BMW look into the valvetronic issues.
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04-24-2018, 10:56 AM	#29
delfunk Private First Class 32 Rep 110 Posts Drives: 2016 M4 GTS Join Date: Apr 2018 Location: Sacramento, CA iTrader: (0)	After taking the car in four times for this BMW finally agreed to reprogram my computer. Here is what the service rep said: "Your concern was that the Valvetronic did not function properly. We did not find any relevant faults stored. We contacted BMW, as per their request we performed programming and complete encoding. Initialized windows. Perform valvetronic test plans and ran without faults. Vehicle is operating to specs." Bem4 maybe they can do this for you? Might help.
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04-26-2018, 07:43 AM	#30
AlpineWhite_F80 Private 82 Rep 96 Posts Drives: 21 G80 M3C, 21 X6 M50 Join Date: Feb 2017 Location: Miami, FL iTrader: (0)	It has happened to me around 2 times in the past 1 1/2 years, and only after hard acceleration then letting go, the car just kept going for a couple seconds. I drive a F80 ZCP
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06-06-2018, 03:54 AM	#33
Raul1428 Registered 0 Rep 1 Posts Drives: 2015 M3 DCT Join Date: Jun 2018 Location: India iTrader: (0)	Any updates on this? Im having the same issue on my 2015 m3. When i go from 100% throttle in 2nd and shift to 3rd and let go of the gas pedal, it continues to accelerate at around 3k-4k rpm, I have to mash the brake for it to stop accelerating. My car is completely stock and it happens in Sport+ with MDM. Also have noticed it happen when im in traffic and trying to do short pulls. I managed to record the incident on my go pro with M lap timer
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06-10-2018, 04:49 AM	#35
BMW9 Second Lieutenant 53 Rep 234 Posts Drives: BMW M4 / Nissan GTR Join Date: Nov 2010 Location: Los Angeles iTrader: (0)	could be a problem with the throttle Controll module.
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09-26-2020, 11:57 AM	#44
White340 Lieutenant Colonel 1392 Rep 1,986 Posts Drives: 2018 M3 Comp / 2022 X5 45e Join Date: Dec 2015 Location: NYC iTrader: (3)	Can you post a video of this? __________________ 2022 X5 45e : AW/Tartufo 2018 M3 Competition : AW/SO 2016 340i xDrive : AW/CR (sold)
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