So I have a 2002 honda civic Dx, it is a standard and makes a high pitched squeal when I'm decelerating. It only occurs when the car is in gear but I am not pressing the accelerator. If I put the car in neutral the squeal stops and it I press the accelerator the squeal stops. It doesn't make the noice at idle either.
The noise started a month or two ago and I dont think it's a major mechanical issue, but it is horribly annoying. Any help would be appreciated. Thanks

 

Try spraying some lithium grease onto the alternator belt and then drive it and see if it goes away or changes frequency. If not, try the power steering belt.

 

What he said ^. My car did same thing except it was my ac belt/pulley.