Hi
This morning a noise started coming from the engine of my 05 1.9 JTD Doblo.

Its kind of a high pitched whine/drone that happens when you use the accelerator its quite loud when pulling off from traffic lights or a junction but not very noticeable when traveling on the open road. The car pulls and drives fine.
It also does not make it when the engine is just ticking over.

Can anyone help with what it might be?

Thanks

if its a squeal sound when engine is under load could be alternator belt slipping. does battey light come on?

thanks,
the battery light does not come, the engine does seem to pull fine also.
the squeal happens when under load, when driving along at 40-50mph I cannot really hear it at all, but that might be the engine noise downing it out. Its quite loud when pulling off from junctions or say traffic lights...