My car starts when you want

I have a 99 Ibiza on several occasions I have gone to start it and it does not start, to start when it comes out of the ... Labateria is fine, the implementation also, the heater also, I have tried to change the key and it remains the same and I keep it and I realize it is what times in which I do not start the luminous witness of the heaters. The keys so many times that I see what I see the signal of the warmers' witness then it is when the car starts. Someone can tell me that it can be the breakdown thanks.

Change the araque engine but first look how you have the dough cable

In the end it was reliable