Sorry if its been covered so many times!!!

I read it today as the EMl was on and emissions message. One of the fuel temp sensor wires was broken. but also got: 17978 engine start blocked by immobilizer p1570 not a plausible signal intermittent.??

iv just got my first vw passat and have the glow plug light flashing prior to starting. seems only if i leave it for a while. If i leave the car for any time at all the glow light flashes before i start and i have to take the key out 2 or more times then it will start. if i try to start it when the light is flashing it will start then die then just crank over.

Any help would be good if you have the time!