I've heard my revs should rise but mine infact drops alittle if anything, doesn't make any change really if it's disconnected it or not.

Could this be the cause of my fuel consumption increase and bogging down at low revs?

possibly suggests the ignition timing is out.

Only just started doing it recently though, been fine for the 5000 miles I've owned it till now.

Can it not suggest the sensor has bust?

Bump