Squealing Noise - Engine Bay

[sponge55]

The car has developed a high pitch squealing noise from the engine bay from cold starts and stops once the engine warms ups.

I have taken it to toyota for them to look at it and all they could find was a leaking water pump which they fixed but the noise is still there.

Before i take time off work to take it to toyota again, has anyone experienced anything similar that can shed some light on what the problem might be so i can give better description on what they should be looking out for?

I dont know if this is a common thing that i dont really need to worry about as the noise foes away once the engine is warm?

Its beginning to annoy me and i expect it to get worse once the weather gets worse.

Thanks

[Mooly]

Usual suspects would be something like the alternator (a bearing) or perhaps a belt tensioner pulley. I had a noise a bit like you describe when I had the Corolla TSport and that was the belt tensioner pulley. I was able to trickle some oil into the bearings down the shaft of a screwdrver and it was silent from then on. Started at 3.5 years old and I sold it at 8 years old.

Toyota must know what it is if you took it to them for that problem to be rectified. I would ask again and if you paid for the water pump say that it hasn't cured the fault you took it in for.