The most likely cause is a switch that is not shutting off the power to the light. Most likely it is one of the switches in the door jams, so check them to make sure they are working by pushing them in and out and watching for the interior light to go on and off.

It’s a fairly straightforward installation without major modification to the car, and there are companies doing it. One we know does it for around $2200 drive in, drive out, and guarantee the rego authorities will accept it when you go to change the engine number.

Try and establish whether or not it's firing during this starting phase. If it isn't you should look for an electrical problem, if it is you should look to the fuel system. On the day it won't start, remove the spark plugs and check them for any wetness that might suggest it could be flooding. I the plugs are black and wet clean and dry them and replace them and try again. If it starts this time I would be looking to the fuel-injectors.