[bwiwy]

Hi guys, i'm new here.


I bought a 2012 520d with 125.000 miles on the clock.
it is the 184 hp with 8 speed automatic (engine code N47D20C)

I live in Denmark, and we have some cold nights right now. (4-5 degrees Celsius)
The first 3-4 minutes of driving i hear a slight version of engine knocking.
I'm not sure what it is, but there is a tapping/knocking sound.
It is not a metal to metal sound, but it is definitely weird.
i can not provoke it in neutral, but when driving at slow speeds and accelerating, there it is.
It slowly fades away, and after 3-4 minutes of driving the car sounds perfect again.

The car runs fantastic, and sounds healthy. And i get some great MPG.
I just did a premature oil change, and cut open the filter, and couldn't find any serious metallic parts or anything.

I have a bit of whining from the v-belt, i just ordered a new belt, tensioner and waterpump, just to be safe.

I also ordered a upper chain tensioner in case of it is the chain making the noise becaus of of a faulty tensioner, it would be a easy fix.

But i'm in the ropes here, not sure of anything.

[ezaircon4jc]

Originally Posted by bwiwy

Hi guys, i'm new here.


I bought a 2012 520d with 125.000 miles on the clock.
it is the 184 hp with 8 speed automatic (engine code N47D20C)

I live in Denmark, and we have some cold nights right now. (4-5 degrees Celsius)
The first 3-4 minutes of driving i hear a slight version of engine knocking.
I'm not sure what it is, but there is a tapping/knocking sound.
It is not a metal to metal sound, but it is definitely weird.
i can not provoke it in neutral, but when driving at slow speeds and accelerating, there it is.
It slowly fades away, and after 3-4 minutes of driving the car sounds perfect again.

The car runs fantastic, and sounds healthy. And i get some great MPG.
I just did a premature oil change, and cut open the filter, and couldn't find any serious metallic parts or anything.

I have a bit of whining from the v-belt, i just ordered a new belt, tensioner and waterpump, just to be safe.

I also ordered a upper chain tensioner in case of it is the chain making the noise becaus of of a faulty tensioner, it would be a easy fix.

But i'm in the ropes here, not sure of anything.

Don't know if this is the case, but I've read that BMW (and other manufacturers') injectors are noisy; maybe more so cold?