What do I need and what process would flash my ecu and put it back to a factory setting. I think it needs some sort of reset as the ecu is not send a signal to number 4 injector. It a continental ecu and a 1.6tdi cayc fabia

If you're lucky and Skoda have released an update for your ECU, you can download the flash file for free and use something like ODIS or VCP to flash it.

 

A Skoda sealer should also be able to flash it but I don't know what they'd charge.

 

Finally, a decent tuner should be able to both backup and restore the software. They can either use a flash file from Skoda (where available) or a backup from another car.

 

No idea if it's likely to fix your issue though...

Now this is getting bizzar the miss fire on 4 has gone and moved to 2