I'm approaching 5000miles in my Monte, 1.2Tsi 105bhp. Has always super smooth sounding with a nice little roar to it

The engine note above 2000rpm has acquired a certain low frequency 'thrum' over the last few hundred miles. The only thing that's changed is a tank of BP Ultimate as opposed to the regular Momentum99. Fuel economy is still good, oil level checks out fine (I've not had to put a drop in it yet?!).

Is this a characteristic of the engine bedding in? Change of fuel? Or something more sinister? Might see if the dealers will have a nose unless they're gonna charge me for the pleasure. Just wondered if any other owners had experienced the same. Sounded lovely before so this bugs me a little

Thanks all

If the new fuel you are using is a different Octane rating then yes you may just detect a small change in the engine note under load at revs. But I think you would have to listen very carefully! This occurs because the ecu changes the engine timing parameters slightly to accommodate the new burning characteristics of the lower or higher octane fuel. Of course you may have another issue, but it's probably nothing to worry about and may just be colder temps causing the change in engine sound dynamics.