My engine has developed an irritating problem, it has started hunting (probably idle control valve sticking?), but sometimes ticks over beautifully at 2200rpm, and sometimes correctly at 800rpm.

In addition, when you slam down the throttle it occasionally just stops dead for a second and then suddenly thows it all at you in one go! Great when cornering.

Do I have separate faults, or one that I haven't diagnosed.

It is a 2.0i Pinto, It has run perfectly for 2500 miles until this weekend.

Any ideas?

injection....

what kind of version wich sensors do you have?

Nearly standard Bosch ?tronic as fitted by uncle henry to the sierra. I have just moved and bits around

Check your plug gaps haven't closed as that can cause these problems. My XR3 used to do it every 2000-2500 miles.