Fiat punto idling high after head gasket done?

[rumpelstiltskin]

Had the head gasket done on my MK1 Punto(oh why oh why did i buy one)and since getting it back when i start it from cold it revs really high(uncomfortably high) for a few seconds then comes down in a few seconds.But even when warm it idles way higher than it used to and is using more fuel?Would the Lambda sensor get damaged with the water flying past it when gasket was away?Symptoms don't seem serious enough for what i've read about a failing Lambda?No dash warning etc.A few people have told me ECU would be confused while gasket was blowing and it would need a while to readjust itself back to normal,but that's about 300 miles now and its still revving high etc?Anyone any ideas?

[wrinx]

Take it back to the garage and complain

wrinx