Strange noise from the engine.....

[Benzadrine]

Hi all - My W204 Kompressors been fine since I bought it , but on arriving to pick my daughter up last night she said the engine sounded very loud on idle and when I switched the engine off, there was a noise that lasted 30 seconds. I also thought there was a smell of burning in the air. I opened the bonnet obviously and everything seemed fine though it was dark with only a phone torch.I drove home and put my diagnostic tool in this morning, no codes and nothing showing up on the instrument panel. I have a video of the motor running, all belts and fans are ok -but noisy-but couldn't upload. Any help is appreciated, Regards

 

[SpikyMikey]

M271 engine?
Timing chains are a known issue.

 

[Benzadrine]

M271 engine?
Timing chains are a known issue.

Not sure about the M271 engine Spiky? Sounds like a big job.......

 

[markjay]

Your car is a pre-facelift W204, so it will likely have the M271 engine, which is known for it's timing chain issues.

 

[Larkone]

OP said - I switched the engine off, there was a noise that lasted 30 seconds.
Not likely to be timing chain noise when the engine is off.
Need to look at what might still be running such as fans/electric motors etc.

 

[Benzadrine]

Your car is a pre-facelift W204, so it will likely have the M271 engine, which is known for it's timing chain issues.

Thanks, markjay

 

[Benzadrine]

OP said - I switched the engine off, there was a noise that lasted 30 seconds.
Not likely to be timing chain noise when the engine is off.
Need to look at what might still be running such as fans/electric motors etc.

You can tell I'm not technical at all...Took it to my local mechanic who spotted it straight away & you were spot on too Larkone. It's the A/C that won't switch off for some reason, said I can still drive the car without any danger of blowing it up lol, but obviously is using more petrol and wants sorting out (if any one has a solution?) Thought it might have shown up on my diagnostic scanner...Thanks again for reply

 

[markjay]

Fan working after the engine has been switched-off is actually normal on the W204..... they all do that.

 

[Benzadrine]

Fan working after the engine has been switched-off is actually normal on the W204..... they all do that.

No, this is something different then as it's not normal -had the car 2yrs plus the mechanic said it's not right ...