Knocking sound when cold start...help

[ssabripo]

Last few days, when I start the car and start to drive, I hear a loud single Knocking sound going from 1st to 2nd gear at around 2500rpm shifts.

It happens once and it happens only when the car is cold, going from 1st to 2nd. Sounds like it is definitely coming from engine and not transmission, but I wonder why it happens when shifting from 1st to 2nd.

Car is a 2011 with DCT, 23k miles.

It never did that until just the last few days.

Any help would be appreciated

[///M Power-Belgium]

Originally Posted by ssabripo

Last few days, when I start the car and start to drive, I hear a loud single Knocking sound going from 1st to 2nd gear at around 2500rpm shifts.

It happens once and it happens only when the car is cold, going from 1st to 2nd. Sounds like it is definitely coming from engine and not transmission, but I wonder why it happens when shifting from 1st to 2nd.

Car is a 2011 with DCT, 23k miles.

It never did that until just the last few days.

Any help would be appreciated

Call tomorrow your BMW dealer and say what you have written here ..
Stop driving your car and wait for answers from your BMW dealer tomorrow !

[serge]

Originally Posted by ssabripo

Last few days, when I start the car and start to drive, I hear a loud single Knocking sound going from 1st to 2nd gear at around 2500rpm shifts.

It happens once and it happens only when the car is cold, going from 1st to 2nd. Sounds like it is definitely coming from engine and not transmission, but I wonder why it happens when shifting from 1st to 2nd.

Car is a 2011 with DCT, 23k miles.

It never did that until just the last few days.

Any help would be appreciated

Same issue here with my 2011 6MT (8k miles); In my case, the sound is coming from the transmission... Took it to the stealership and they said the car was ok. Go figure...