My new Fiesta doesn't handle well on highways above about 80kph, it tends to go off line and I have to make constant steering corrections, as if its been blown around by the wind.

The garage told me that it could be alignment but it doesn't feel at all like this to me? I have to concentrate hard and to make things worse the steering is super direct; no more than a slight turn is needed.

It has done only 4000 kms and I have never hit a kerb, the tyre pressures are correct as well.

The dealer told me to get the alignment checked in a garage opposite and it's not covered by Ford warranty over 2500 kms.

Not wanting to waste my money; any advice of a possible cause would be appreciated!