Got my engine back in the cos, and running last night. yey!

BUT, it has a slight problem.

When idleing, its smooth and runs nicely, but when you apply any throttle, it coughs and spits around.

Now, if you hold it at a certain rev point, i.e, 3k, it will rev nicely, but when you go to put any more or less on again, it does the same thing.

And when you come completely off, it idles fine again.

The car has been sat in the garage since last september, so i was wondering if it could be dodgy fuel?

I have a set of NGK BCR8ES plugs from Halfords in it for now, as i just wanted to get it started up. Could it be those?

Ive got some 071c's and new fuel to try tonight, if these dont help, any ideas?

Crank sensor is gapped correctly also.

Thanks
Mike