Complete loss of power

[umfau]

Has anyone experience complete power loss for 3-5 seconds at any force acceleration? Almost feels like fuel is completely not going to engine and car just pauses

The car has comp package and all stock.

Dealer has no clue what is going as no error codes are generated. Was hoping someone of forum could help.

[josec70]

Originally Posted by umfau

Has anyone experience complete power loss for 3-5 seconds at any force acceleration? Almost feels like fuel is completely not going to engine and car just pauses

The car has comp package and all stock.

Dealer has no clue what is going as no error codes are generated. Was hoping someone of forum could help.

Was it straight line acceleration or coming out of a turn? Also, what traction mode (on,MDM, off)?

Could it have been traction control related?

[umfau]

It's happens in straight line and on turns (less on turns). I have experienced it in complete comfort mode cruising at 40 mph or on hard acceleration in all sport plus mode.

Issue is very strange as I have not been able to pinpoint to one type of driving or setting on the car.

[Charlie_Big_Potato]

Check the battery connections. I had the same issue with my e46 a while back and the battery wasn't making a good connection. It's a long shot but that was the problem I experienced

[Dumpspec]

also check your exhaust vacuum lines. i had a slash in one my exhaust lines that caused loss of power. not sure how it happened but after line was replaced car felt normal again.

[umfau]

Thanks guys ... my major issue is bmw dealer does not want to look at the car until they either see a fault error code pop up or they notice the issue during test drive. Since problem is so random on a short test drive they will probably never see it.

So now I am stock with the problem and dealer pretty much saying they can't do anything even though the car is under MFG warranty still. I have already escalated to BMw of NA but I don't expect much to happen.

Why I resorted to fellow M5 owners to see if anyone else has seen this before. I will look into the two items raised here. Any other thoughts is greatly appreciated.

[VoytekM5]

check the vacuum lines to the exhaust valves.

[fkim119]

If it's coming out of a turn at hard throttle, it's the traction control.

[josec70]

Originally Posted by umfau

It's happens in straight line and on turns (less on turns). I have experienced it in complete comfort mode cruising at 40 mph or on hard acceleration in all sport plus mode.

Issue is very strange as I have not been able to pinpoint to one type of driving or setting on the car.

I would try driving w/ tc off for a few days to eliminate this as a cause. I suspect that's not it since it's happening during relatively light acceleration.

As others have suggested you may want to check vacuum lines on exhaust.

[umfau]

Thanks guys .... it's not traction control kicking in ... I have a service appointment setup to take in and BMW NA is trying to help with dealer as well. Thanks for the suggestions. Will let you guys know what they find.

[Mcc420]

Get yourself a logging tool (jb4,bm3,bmw logger,etc). Then you would be able to see what's going on and post it for others to see and help. Actually there should be a sub-forum on this forum.

[umfau]

Wanted to provide update to all ... I was able to capture on my GoPro the issue and the dealer finally agreed there is an issue.

After having the car for week they came back and stated my transmission needs to be replaced.

I am happy at least that finally after complaining for over 6 months they root cause the problem and are now ordering me a new transmission and replacing it.

[josec70]

Originally Posted by umfau

Wanted to provide update to all ... I was able to capture on my GoPro the issue and the dealer finally agreed there is an issue.

After having the car for week they came back and stated my transmission needs to be replaced.

I am happy at least that finally after complaining for over 6 months they root cause the problem and are now ordering me a new transmission and replacing it.

Awesome you got it on the Go Pro and even better you're getting a new tranny!!!!

[DingolfingLove]

I had something similar.... no warning codes, errors or lights...just suddenly had the power of a Prius. I had driven normally, without any WOT for 30 miles (in perfect dry weather) and everything was normal, stopped for 4 hrs, went to drive home and it felt like I had lost 450bhp. It stayed like this for x2 days and then all came back. It could possibly have been caused by a fuel contamination/quality issue. One cause I thought of is that it could have been due to having a build up of condensation in the fuel tank, i.e. leaving the car overnight with low fuel levels. I have always left the car with at least a 1/3rd of a tank in it & it has not done it since.

[///3dkn]

Originally Posted by umfau

Wanted to provide update to all ... I was able to capture on my GoPro the issue and the dealer finally agreed there is an issue.

After having the car for week they came back and stated my transmission needs to be replaced.

I am happy at least that finally after complaining for over 6 months they root cause the problem and are now ordering me a new transmission and replacing it.

I know you're getting a new tranny but would you mind uploading the video for others to see in case they end up having a similar issue and have something to compare it to?

[TopEnd]

what specifically was the issue with the tranny?