i am having trouble with my astra gsi. i had problems before with it not firing up but i got it going eventually. now ive just tried to go out in it and it wont fire up at all now. i dont have the means to look at the fault codes so could any one please suggest any things for me to look at first. it just turns over and over and over again dunno what to do next. ive cleaned all the sensors apart from the crank sensor.