Sorry, after reading and testing the code, it works perfectly.
And regards to the starter motor timeout, yes, i need to add a timeout if it won't start, as in the rare occurence the car refuses to start, i don't want it burning out the starter motor.
This is awesome, thank you so much!
I've just ordered the sparkfun GSM shield, when it arrives, i shall attempt to get it to work with this.
Regards, Matt.