1998 renault megan scenic?petrol?

hi i have got a above motor the problem is it wont start i was wondering if it is coil took plug out but no spark there is power to coil had a tester on it and there is power to coil the imobaliser works as it should the battery is flat at moment but had leads on from my transit its turning over ok it just like a car that has run out of petrol can anybody help