The 1.4 12V engine is dire on fuel consumption. It's a well known fact.
However some 1.4's seem to be OK, whereas the majority of them tend to be terrible.
I used to have a 1.4 myself, and it averaged about 18MPG.
Bahney has a 1.4 and his averages about 15MPG. (170 Miles to a full tank). That really is dire!
If you get anything over 30MPG, count yourself lucky.
The only other alternative to getting better MPG in your 1.4 would be to sell it unfortunately as there's no quick fix. I've now got a 1.2 16V and it returns about 46MPG as I travel 50 miles to work and 80% of it is motorway.