Strange Noise From A4 1.9TDi - Thoughts?

[chrisash32]

Hi Everyone,
Just after some advice if you wouldn't mind!
My B6 TDi has started to make a strange loud noise when the engine is under any load. It appears to be coming from the front of the engine but I cannot pin point it.
It was advised that it was my alternator pulley but this has been replaced and did not fix the issue.

Here is a small video of the problem:



Many Thanks in advance.

Chris

 

[yendall24]

check your aircon compressor clutch had this sound on a b5 thats what it turned out to be

 

[stu_m]

I was going to say the same thing even though I haven't listened to the noise!

Mine is a bit noisy it gets worse with econ pressed

 

[chrisash32]

Thanks for the reply! Can I fix the clutch on its own or do I have to replace the full compressor?


Thanks

 

[666markyboy]

Sorry i can't help you other than to say when i first got my car i had to store it in the garage for 2 or 3 months before i put it on the road..... i found that if i didn't run the engine for a couple of weeks or more then when i first started it i got the exact same noise your having from the same area... after running for a couple of mins the noise went away and now i drive it as a daily i've never heard it since.... i can only imagine something was getting dry due to being left a long time.... i'm doing the cambelt in a couple of weeks so hope to have all the front end stripped off and will be investigating things like the aircon pump and alternator

 

[Willf]

Sounds pretty bad - although I suspect it sounds worse than it is!
I would go with the suggestions - it does sound like something running off the aux belt. Have you tried running it without the belt connected? Could be something simple like the tensioner...

If it shuts up - you know its something that runs off that belt.

Otherwise its on the cambelt - tensioner or water pump beraing etc... Either way, I wouldnt be driving it until its diagnosed!

 

[stu_m]

now after listening to the noise on the vid i would say its not the clutch pulley on the compressor!!

it sounds really bad to me in the vid

what sort of service history does the car have? how many miles? what oil has been used?

just thinking if it could be worn cam lobes but then it should be noisy all the time!

 

[chrisash32]

Hello!
Full service history on the car, done every 10k. Nearly 130k on the clock and I have owned it since 60k (3 years).
Had cam belt kit, water pump, aux belt, alternator pulley etc done last year. The noise was briefly there before that (once or twice) but has gradually got worse since to the point where it is at now.

Its not something that has just started, Been aware of it for a good 9 months.. its just gradually got worse and worse.

Engine appears to run fine and has been chipped since the day I took delivery.

 

[kevbu]

Is anything hitting blades of the fan?

 

[Willf]

Hello!Full service history on the car, done every 10k. Nearly 130k on the clock and I have owned it since 60k (3 years).Had cam belt kit, water pump, aux belt, alternator pulley etc done last year. The noise was briefly there before that (once or twice) but has gradually got worse since to the point where it is at now.Its not something that has just started, Been aware of it for a good 9 months.. its just gradually got worse and worse.Engine appears to run fine and has been chipped since the day I took delivery.

Its been there for 9 months?? I would have got it sorted as soon as I heard it!!It does sound pretty catastrphic on hearing it again - it could have done untold damage over the course of the nine months....It almost sounds as if the oil pressure is momentarily dropping off!

 

[Mike.M]

The first thing that I though of was a failing or failed aux belt tensioner.

 

[666markyboy]

as mentioned earlier.... take the aux belt off and see if it still does it