fiat Punto seems to misfire

[saintpaul10]

i have a 1.2 51 plate fiat punto mia. I have just started to get problems with it , when she gets warm she starts to misfire loose power and eventually comes to a stop if i let it. However i have changed the two coils, the ht leads & the spark plugs but it still does it, She starts & runs fine on short journeys but i 1st noticed this when i went 60 mph in it as i ahve only had it since xmas 2010 any ideas,

[AlBags]

Unlikely .. but Fuel Filter?

[jefp1938]

Could be your choke is sticking on and flooding the plugs, is it heavy on fuel? It could be the ignition isn't being advanced as you speed up, I would suggest getting it tested on a rolling road, they should be able to tell you what the problem is from the readout.

[AlBags]

Choke? Rolling Road? lol

No choke on a cat injection car.

[TWR]

Check the connection from the end of the H.T.Leads to the plugs + Coil Pack.