Help!! my passat is ill :(

[Crackman 619]

Just got back form Birmingham airport..driving down the motorway then all of a sudden the coil light starts flashing and engine fault comes up on the vda not only that I lost all the power to my car (think it went into limp mode bit scary wen im going 70ish)

So i stopped in the hard shoulder turned off engine waited turned back on and everything was fine..Then i was driving along went over 70 and the fault came back on again..sooo went hard shoulder restarted never drove over 70mph and all was fine..

Does anyone know what it could be? my coolant levels were very low the week before so i topped up to top line..will check again in abit.

Help very much appreciated.

Edit: just checked coolant and its just under the top line...think its time to ring vw tomorow.