[HasanK]

Hello everyone, I'm afraid that my car seems to have caught some sort of a drivetrain issue and I won't be able to find out exactly what is wrong until next week. 'Till then, it's parked .

As I was going to work in the morning, at one point I accelerated hard and the engine seemed to start making weird noises. The power delivery wasn't something I was used to. After taking the car to the quick service center, I was advised to take it to the main service (that usually isn't a good sign).

Symptoms thus far are:

• Louder exhaust noise inside cabin
• Subtle rasping noise when above 50kph and 2000RPM
• Weird gearbox shifting (not downshifting like usual)
• Engine vibration is visible when idle and standstill
• At idle, RPM's go up and down (+/- 500 RPM)
• Engine "choked" when I switched from comfort to sport at standstill
• No engine check light, or any warnings from the system

Vehicle Details:

• F20 M135i
• N55 Engine
• Production Date: March 08 2013
• 8 Speed Automatic

Has anyone experienced any of these symptoms? Does anyone know what the possible cause could be? I would appreciate any feedback.

[chaddy74]

Thats really disappointing !! Hope its nothing major. Keep us posted

[TitanNut88]

Mine gives a drivetrain error too, but with different symptoms.

I don't know if it can be done, but I paste a link to another forum thread where people are having symptoms quite similar to yours.

http://www.babybmw.net/viewtopic.php?f=74&t=59323

Hope it helps.

[westphone]

I hope you find a complete solution~~~

[ttimbo]

On a complex cars such as the M135i, which has multiple sensors, it could be any one of a number of things. Dealers have the diagnostic tools, and you have warranty for this sort of thing. Let us know the outcome

[iskoro]

Have the same symptoms together with drivetrain error. The reason was simple: no gas in the tank. Failure of fuel level sensor had been diagnosed by dealer and the whole tank has been replaced.

I had this problem twice after that: once on ¼ full tank during the rapid acceleration and second time last week after driving for 450 km on cruise on eco-pro mode (the car said it still has more than ¼ tank full and range about 170 km)

[HasanK]

Originally Posted by Robopilingui

Mine gives a drivetrain error too, but with different symptoms.

I don't know if it can be done, but I paste a link to another forum thread where people are having symptoms quite similar to yours.

http://www.babybmw.net/viewtopic.php?f=74&t=59323

Hope it helps.

Cheers, I'll have a look into that.

Originally Posted by iskoro

Have the same symptoms together with drivetrain error. The reason was simple: no gas in the tank. Failure of fuel level sensor had been diagnosed by dealer and the whole tank has been replaced.

I had this problem twice after that: once on ¼ full tank during the rapid acceleration and second time last week after driving for 450 km on cruise on eco-pro mode (the car said it still has more than ¼ tank full and range about 170 km)

I don't think it's a fuel problem, I filled the car up Thursday afternoon. (Didn't drive on Friday), it's got a good amount of fuel in it. But if it is a fuel level sensor and it's playing around with the fuel pump, then that could make sense.


A part of me really feels as if something just broke; or gave in when I accelerated. It was a sudden change of character, and wildly unexpected.

Thanks to everyone for the good wishes (). I'll post updates when I get them. I'm hoping it's something stupid like bad fuel or a loose wire or something!

[bennzwel]

This might not be related to your problem at all , but weird enough I had the exact same issues with my Opel Corsa few years ago. Almost shared 90% of your symptoms and it ended up to be MAF sensor ( no error codes were showing when doing self diagnosis in the car )



Hope yours is something like that and not a serious issue.

[HasanK]

Took the car in today. They believe it's a misfire and will take a week to fix. Tomorrow I'll get a detailed update.

Bad news thus far is I wasn't given a replacement vehicle.

[HasanK]

Update 2: The engine suffered from an "air-charger failure". This is the first time I hear of this part. It's supposedly connected to the turbocharger.

Bad news is that the part will take 2 weeks to arrive, and then some for installation.

Anyone know what the exact function of the air-charger is?