VN is stumbling on coming to stop

[vn2nv]

When I drive my vn and then come to a stop at the traffic lights or whatever, it begins to stumble at low rpm and almost stalls. Then when it aligns level again when completely stopped, it goes back into 800 to 1000 rpm. I am getting very bad fuel economy too and no power like it used to have. Oxygen sensor is replaced.
What could be doing this?
Any help greatly appreciated!

[mouce]

Check your fault codes. Could be a dodgy idle air control valve.

More than likely, a dodgy ignition lead, or maybe a coil pack on the way out. Check those out first.

[vn2nv]

yeah the fuel pump is not making as much noise as it used to. It is very silent and you can just hear it. Before, it used to make a whirring sound when you turn the key, now there is no such sound.