[VeloceRagno]

As title says - annoying whining noise from either underneath or right front -
- goes up and down depending on road speed
- only when car is cold
- sometimes goes away quickly after just 1 or 2 miles - sometimes after 5 miles (but always goes away)
- almost sounds like older cars with a slipping fan belt (but it's definitely not a belt - sounds too mechanical to be a slipping belt and a belt noise won't increase as road speed increases)
- annoying and embarrassing!

Wheel bearing? Can a wheel bearing make a high pitched noise?
Can it be clutch related (altough if I disengage or engage clutch , noise stays the same)
Can it be brake disc or pad related?
And if any of the above, why does it go away after a few miles?

 

[OldSmokey159]

Guess it could be a number things as you suggest but the water pump is in that area and they omit a similar noise when bearings are shot. I believe water pump failure is what causes the timing belt to 'let go' and if I were you I might be inclined to get it professionally diagnosed just for peace of mind.

Good luck

 

[VeloceRagno]

Interesting - water pump would have been my last guess.
As I said - the sound increases as the road speed increases - and stops when the car is stationery - wouldn't the water pump continue making a noise when the car isn't moving?

 

[OldSmokey159]

Interesting - water pump would have been my last guess.
As I said - the sound increases as the road speed increases - and stops when the car is stationery - wouldn't the water pump continue making a noise when the car isn't moving?

The pump can omit less noise when stationary or at slower speeds and generally increases as the bearings dry out/rust . I've not suffered this on the Alfa personally but I have on other vehicles. Water pumps seem to be a bit of an Achilles hill and certainly worth checking.

wheel bearings rumble and the noise changes with distribution of weight. Screeching is unusual but not impossible.

Might be inclined to pop the car up on a jack and do some basic checks if you haven't already.

 

[Old Engineer]

I doubt it is water pump. It's easy to isolate an engine or 'road speed' noise just by knocking it in neutral at the critical speed. If it the noise goes then it's engine. If it stays it's a chassis problem. Might be a wheel bearing which will vary as you load it. Take it to about 25MPH and swerve to load up each side. A wheel bearing will give a wha wha sound. Could also be a drive shaft bearing but that's more difficult to find.

Also a stone in the brake disc can give these symptoms. Again it won't go away if you knock it into neutral. But it would change if you lightly press the pedal.

 

[halftone]

From the OP description I'd suspect steering pump or fluid, but noise varying with road speed doesn't seem consistent with that theory. Still, perhaps it's worth operating the steering when cold and stationary to see whether the noise is affected.