Fabia 1.4 MPI - Rotational Noise from Cold Start?

[StevenP]

Hi there,

 

Our Fabia 1.4 MPI has been gradually developing a rotational noise that's getting progressively worse, which is occurring from cold start (or after it's been sitting for 3/4 hours). It sounds like it's coming from the aux belt area (it doesn't seem to me as if it's timing chain, as it's not excessively rattly). It goes after about 2-3 minutes of running, after a 10 minute drive its completely normal. Could this be a pulley/idler wearing or perhaps even the belt itself? Is there a common failure in this area?

 

I've attached a video from cold start, it's a couple of minutes long to compare the sound from the beginning/towards end.

 

Any help with the diagnosis would be great, I guess the next port of call would be to take the aux belt off and see if it still makes the noise but wondered if anyone recognised it!

 

 

 

Cheers,

Steve

Edited 11 August, 2013 by StevenP

[LGM]

What's the mileage on your car? I kept getting a rattle from my car and the chain was stretched, although it was on 109k, now it's been changed its no were near as loud.

[StevenP]

It's only done 70k miles. I could understand perhaps a bit of rattle, but it just doesn't seem like it's that to me - if the chain was stretched it'd do it all the time - it's also perfectly quiet after the first few minutes, although I suppose I can't rule it out

[StevenP]

Bump.. any other ideas?

[waool1988]

I have the same issue but I have not given it attention yet because it isn't obvious enough to know were the problems is   ....   mine is around 56K

[StevenP]

Atleast there's someone with the same problem

[waool1988]

Unfortunately! :P  ...  Let me know what happens with you if it propagates

[StevenP]

Will do! It hasn't really got a lot worse in the last 10k miles - I reckon it could be alternator clutch pulley?! But not sure and it's pretty hard to diagnose given that it only does it for a few minutes when cold (by the time you've driven to a garage for example, it stops completely!)

[Taylor93]

From seeing the video, and also having experiance of a very loose timnig chain, IMO it sounds more like a fault with a component on the AUX belt which drives:

 

Water Pump (at the top/rear of the engine)

Pulley

Crankshaft pulley

Alternator

Auto Tensioner

AC Pump.

 

To eliminate certain components get a large Screwdriver and with the engine running, put the screwdriver to the component and your ear to the other end. listen for any rough rumbles.

 

Without seeing it myself, I would guess either A/C compressor, Water Pump or the Alternator.

[sepulchrave]

I guess the tensioner, easy to check, spray with WD40 (while the engine is off of course!) and see if it's quieter afterwards. If quieter then replace it.

[StevenP]

Thanks for the input guys, I shall try both methods to try and narrow this down - I did also wonder whether it could be the tensioner as I had similar noises from my S60 D5 which was cured by replacing that. I'll report back with findings once there's a break in the rain!