Corsa won't start with key but bump starts?!?!?

[Rhysoverton]

So i recently began having some ignition problems with my Corsa B club 5dr, it would not start after i had made a journey in the car and i would have to leave it for around 30 mins till it would start again. I then noticed that sometime while driving, it would just cut out and i would have to bump start it as i was going along. I researched into this and read that a lot of people have had this problem and it was due to the Crank Sensor needing replacing. I have now replaced this and still the problem continues.

I have also changed the starter motor, idle control valve and the coil pack but the problem still hasn't been solved. The car will bump start with no problems at all but as soon as the key is turned, the starter motor can be heard turning but it won't fire the engine.

We have checked for a spark on the plugs and non of them are producing a spark when the key is turned which leads us to believe that it could be an ignition problem as when i bump start the car, it runs absolutely fine until it tries to cut out on the odd occasion but when the key is turned, only the starter motor can be heard and nothing else happens.

Also, we hooked it up to a diagnostics and it says that the problem could be the crank sensor or mass airflow sensor. We replace the crank sensor and it isn't the mass airflow sensor as we tested this.

If someone could please help me with this issue.

Many Thanks, Rhys.

[johnny]

First how did.you test the maf? I didnt know you could,

When where the spark plugs last changed? When you bought a new coil pack did you buy genuine or generic? And same for the crank shaft sensor

[Rhysoverton]

Thanks for the reply. All parts were genuine and were pretty sure it's now something to do with the ECU. Going to try my other key which has the chip in it later on to see if its something simple like that.

[johnny]

If the engine cranks its not the key, theres 4 things needed to start the car, i) working altenator to give enough power, ii) starter to kick in and speed up the cranking, iii) fuel, iv) a spark to light the fuel

So what have/havnt you got ?

[Rhysoverton]

I have fuel, a working starter and working spark plugs but they don't do anything when I turn the key and no power goes to the coil pack uess I push start the car and then there is 12v. And my alternator is fine as the battery charges fine I guess :S

[johnny]

Bump start the car and read the the battery anything under 13.6v and the altenator isnt doing its job

Take a reading of the battery without starting, ive seen cars not start with 10v so it has to be very close to 12v