Hard to start, have to hold down throttle, it.

Hard to start, have to hold down throttle, it is throttle body injection, using a lot of fuel so. I replaced the coolant sensor made no difference to make it any better had to turn the distributor about 25 mm then I put a second hand computer in it and still the same, doesn't want to take the throttle down low but once a few revs on it seems ok until you pull up idles rough and will stall sometimes but then the revs pick up and seems ok. Mark