N55 DCT stalling/dying at idle

[e36addict]

My car has this issue intermittently, and clearing the throttle adaptations via JB4 cures it for quite some time. The delay when coming to a slow roll and trying to accelerate is still there however..

I have my mothers 2011 DCT in right now, created a PuMA case for all the same issues, ended up pulling the trans and replacing the mechatronics (internal control unit) and all of the issues seem cured. I'll let the car go for a few weeks and we'll see if it's a real fix. Everything so far seems only temporary.

[jmz135]

Just an update:

I've been driving the car for about 3 weeks since I had the latest software updated.

The low RPM lurchiness and stalling is completely gone. However, the throttle hesitation when decelerating and then trying to accelerate is still there. It DOES happens less often than it used to, but still semi-regularly occurs.

It's definitely software related, half the time the throttle response is instant, the other half there is a 1-2 second delay. It's like BMW understood the problem and it seems like they did try and fix it, but just couldn't QUITE do it.

[mitch55]

I've been having these same issues regarding power surging at idle and throttle delay. Seems to be really bad with AC on. Already have taken the car into the dealership for this problem once before and they told me they could not replicate the problem. It does it all the time!

I'm really tired of this issue and can't even use my AC because of it. Going to take the car in again tomorrow and bring up the throttle adaptations and software update.

[Nifty]

Originally Posted by mitch55

I've been having these same issues regarding power surging at idle and throttle delay. Seems to be really bad with AC on. Already have taken the car into the dealership for this problem once before and they told me they could not replicate the problem. It does it all the time!

I'm really tired of this issue and can't even use my AC because of it. Going to take the car in again tomorrow and bring up the throttle adaptations and software update.

For the past 5 months I've been having stalling, idle, and lag issues that dealers could not explain nor fix (had all DME and transmissions updates as well). Finally after my last visit I happened to speak with the shop foreman who know his stuff. I just got my car back two days ago after they did a Transmission adaption reset and all my issues seem to be fixed. My idle is now rock solid and the throttle lag as been greatly improved. I posted a few days ago in this thread with some more specifics, so check it out to see if it applies to your case. If it does, you might want to go down that route.

[jmz135]

Originally Posted by Nifty

For the past 5 months I've been having stalling, idle, and lag issues that dealers could not explain nor fix (had all DME and transmissions updates as well). Finally after my last visit I happened to speak with the shop foreman who know his stuff. I just got my car back two days ago after they did a Transmission adaption reset and all my issues seem to be fixed. My idle is now rock solid and the throttle lag as been greatly improved. I posted a few days ago in this thread with some more specifics, so check it out to see if it applies to your case. If it does, you might want to go down that route.

I'm wondering whether all these people reporting the problem fixed after receiving the software update were really just experiencing the effects of the adaptive transmission reset that happens when they do a DME update...only to have the problem slowly come back over time.

It seems like the DME update in question definitely fixes the low RPM driving and stalling, but I'm thinking the throttle response issues might not actually be fixed by the update, but seemed better as a side effect of the tranny reset.

[Nifty]

Originally Posted by jmz135

I'm wondering whether all these people reporting the problem fixed after receiving the software update were really just experiencing the effects of the adaptive transmission reset that happens when they do a DME update...only to have the problem slowly come back over time.

It seems like the DME update in question definitely fixes the low RPM driving and stalling, but I'm thinking the throttle response issues might not actually be fixed by the update, but seemed better as a side effect of the tranny reset.

I had my cars DME updated to the latest version in addition to the transmission specific update, and neither one of them solved the problems I was having at idle or with lag. Only when they reset the transmission adaptions did my issues get better. The foreman flat out said that the DME and transmission didn't "talk" to each other correctly and that the reset was only temporary.

Obviously everyone's situation is a bit different, but I wanted to give a heads up to anyone still having problems who hasn't had the reset done.

[pushculture]

Figured I'd share my experience since it mirrors the frustrations you all have been going through. My '11 DCT with 30k miles had the severe throttle lag from stop, RPM hunting between 600 and 1000 while idling, and occasional stalls when cold (especially dangerous since my typical drive begins with a left turn across 2 lanes of live traffic).

It took 3 trips to the dealer before I had the DME updated per the SIB (apparently they had to get special approval from BMW to install it since mine is an early-build '11).

The stalling is gone. The lag from stop is gone, though there is still bad low speed hesitation (say, accelerating in traffic beginning at 10mph). Idle RPMs were spot-on at 700 RPM for the first 1000 miles or so after the update, but then I guess adaptation got the best of things and they now bounce around between 600 and 700 -- not as bad as before the update, but a little rough.

The overall feeling was of far less power than before the update. I really missed the old power and decided to try a Dinan tune to see if I could get the feel back. The difference on the highway and above 3000 RPM is dramatic and the power boost is intoxicating. Unfortunately, the tune has had little effect at low speeds and below 3000 RPM, where the car feels sluggish and not all that different from stock. It actually reminds me a lot of how early Honda VTEC engines felt as you passed the value-timing change point.

One thing I've noticed is that the car has become quite sensitive to the fuel I put in. I had to put 91 octane in on a trip to the boonies with no other gas stations around (around here, most premium is 93), and the car idled roughly and felt quite down on power for the whole tank. Running that tank empty and filling up with 93 restored power and smoothness.

My next step seems to be to try a walnut blast on the intake valves. The car only has 30k miles so from what I've read that's on the low side for needing that done -- and it pains me to spend maintenance $$$ on a car that's still under warranty and "free" maintenance (apparently BMW rarely picks up the tab for intake valves).

I'm nearing the end of the warranty so not having a smooth-running car is making me anxious about keeping it. I have the feeling that what we're dealing with is something that BMW needs to fix with another firmware update -- though if they'd like to give us all replacement M235i's, I wouldn't say "no" ;-)

[mitch55]

Well I got a call back from BMW. Again, they claim they couldn't replicate the problem even though it does it all the time. Now they tell me they cant diagnose anything until I return it back to stock. The vehicle was sitting at the dealership for 4 days only for them to tell me they don't want to touch the car.

Will post back after I try a different dealership.

[iuhutch]

Originally Posted by mitch55

Well I got a call back from BMW. Again, they claim they couldn't replicate the problem even though it does it all the time. Now they tell me they cant diagnose anything until I return it back to stock. The vehicle was sitting at the dealership for 4 days only for them to tell me they don't want to touch the car.

Will post back after I try a different dealership.

Pretty standard...i've seen it multiple times and you are even lucky they gave you the option. The SA can flag a customer and then they get super anal about troubleshooting any issue to a mod related part.

Can read JB4 codes that are stored by multiple memory sets (standard tuner codes) and can detect number of dme flashes per the cobb side.

[cheshirecat79]

Originally Posted by mitch55

Well I got a call back from BMW. Again, they claim they couldn't replicate the problem even though it does it all the time. Now they tell me they cant diagnose anything until I return it back to stock. The vehicle was sitting at the dealership for 4 days only for them to tell me they don't want to touch the car.
Will post back after I try a different dealership.

Get in the vehicle with the tech and show him the problem first-hand.

[trainerjon]

Anyone tried this? Not sure if this will work with N55 DCT, but it's probably worth a try?

[Nifty]

Originally Posted by trainerjon

Anyone tried this? Not sure if this will work with N55 DCT, but it's probably worth a try?

This does not work for Transmission Adaptation Resets (I tried this before actually having one done). I actually think this is the process for a throttle reset.

I don't believe there is a DIY for the transmission adaptation reset since even the technicians at my dealership had to wait for a BMW field engineer to actually preform one.

[mitch55]

Took my car to my local performance shop and they flashed SIB 12 09 12 and reset the transmission adaptations. Unfortunately I'm still having rpm surging and rough idle with the AC on. Hoping for another solution..

[trainerjon]

that's a bummer. I hope there's a fix soon!

[lo-tek]

Originally Posted by trainerjon

that's a bummer. I hope there's a fix soon!

it seems to help mine when it's getting jerky lurchy again.

I've had the SIB flash for my transmission though.

[adidoman]

I'm new to this thread. I have a '11 DCT, and it is completely stock. I've been experiencing all of these problems as well and I still have problems with the idle being rough and the RPMs still moving, whether I had the A/C on or off.

I've had the coils replaced, sparks replaced, mass air flow sensor replaced, new HPFP, the newest programming that was available which reset the adaptations, new charge pipe, and carbon blasting the intake and valves, all within the past year with me owning it. I only put good premium gas in my car, and doesn't matter which gas I use, as they tried to start blaming it on bad gas until I told them that.

I've been trying to find some answers for why its still happening to my car and the dealership is running out of ideas and is saying that it is "normal" and a common characteristic of the vehicle. I'm getting extremely frustrated at this point. Some of the replacements, cleaning, and programming have helped the issue. It won't stall anymore, but it still has the rough idle and RPMs coming about only 200 RPMs now, which is a lot less

[jdotketamine]

I'm having the same issue... Only before the car reaches full operating temp. After that the car runs beautifully.

Took it in recently to a reputable bmw/euro shop in the area. I was told the 'injectors in this car are known to leak. The rough idle is from excess fuel in the combustion chambers which burns off' etc.

Has anyone heard of this? Does this sound reasonable?

[CrustyNoodle]

Originally Posted by jdotketamine

I'm having the same issue... Only before the car reaches full operating temp. After that the car runs beautifully.

Took it in recently to a reputable bmw/euro shop in the area. I was told the 'injectors in this car are known to leak. The rough idle is from excess fuel in the combustion chambers which burns off' etc.

Has anyone heard of this? Does this sound reasonable?

It might be reasonable if you had an N54 but I have never heard of injector problems with the N55. Maybe I'm the ignorant one?

[jdotketamine]

Originally Posted by CrustyNoodle

It might be reasonable if you had an N54 but I have never heard of injector problems with the N55. Maybe I'm the ignorant one?

That's what I said. They think I'm an idiot. I feel like the jerky-ness is somewhat dependent on what petrol station I visit...

I also happen to have two intermittent codes... Both seem related to o2 sensors..
P2096 Post Catalyst Fuel Trim System Too Lean Bank 1
P2196 BMW - O2 Sensor Signal Stuck Rich Bank 1 Sensor 1

Sorry to thread jack. Any ideas would be appreciated.

[135iDCTFan]

Any additional news/comments on this??

I just experienced the DCT RPM drop problems (while coming to stop w/out stall) this morning. I had the rough (but stable) idle (hot and cold) for a while before that. Also, my rpms would smoothly rise to around 1,000 rpm or so when I came to a stop and then settle around 700 afterwards. No other real issues that I noticed so I was not too concerned about the single 1,000 rpm rise....that changed this morning obviously.

I think I had the latest SIB update installed with the PPK over a year ago (at 14K), now I just hit 20K and outside BMW warranty (of course). I obviously don't want to replace the plugs, injectors, HPFP, coils, etc. if this won't help. Maybe I'll try to reset the trans first??

[Art]

Hey guys, just came across this thread after my car died on me again today and caused a scare as I got stuck in the middle of a intersection. Good thing that it had died enough times before that I recognized it and got it started right away...

So I saw the SIB link, which was annoying because I described the exact symptom last time I was in the dealership and the foreman claimed he didn't know anything about it.... Sigh...

I did go in to get the VANOS recall done and assumed they'd also update all the DME at the same time. Given that the TSB came out in April of '13, can I assume when they did the VANOS recall in April of '14, it should contain the fix for this as well?

The problem though is it doesn't seem like it had any effects even after the new software last year...

It's a '11 135i, DCT with only 22k miles....

[turbo v6]

Originally Posted by 135iDCTFan

Any additional news/comments on this??

I just experienced the DCT RPM drop problems (while coming to stop w/out stall) this morning. I had the rough (but stable) idle (hot and cold) for a while before that. Also, my rpms would smoothly rise to around 1,000 rpm or so when I came to a stop and then settle around 700 afterwards. No other real issues that I noticed so I was not too concerned about the single 1,000 rpm rise....that changed this morning obviously.

I think I had the latest SIB update installed with the PPK over a year ago (at 14K), now I just hit 20K and outside BMW warranty (of course). I obviously don't want to replace the plugs, injectors, HPFP, coils, etc. if this won't help. Maybe I'll try to reset the trans first??

Follow this link: http://www.1addicts.com/forums/showt...1033690&page=3

The service advisor did not know about this either but, the mechanic found it in the system. Idle fluctuating at stop. Service bulletin 12-15-14.