ECU forgetting fault diagnostic codes? Holden OBD2

Hi there.
I have scanned My car for fault codes using OBD car doctor and free version and Torque.
First they would not pick up the faults and a couple of times they did.
I have scanned the ECU for faults maybe 40 or more times and its come up with codes maybe 5 times.
I downloaded full advanced software and they arnt picking up codes at all.
There are no current, pending or past codes.
Im thinking my ECU is forgetting the codes.
The code I did get those few times was P0606.
I Was driving my car and the engine light comes on and I have no acceleration.
Im guessing this is my cars version of limp mode.
My car is a Holden Epica 2007 CDX on petrol.
Any help would be much appreciated!

I just got a P0605 reading.
But the P0606 is current.

It's quite possible that your ECU is having problems. Those OBD-II codes point to an internal ECU Read Only Memory (ROM) fault and an ECU Processor fault.

I'm not sure what the in-service date of your Holden is, or the same "emissions" warranties apply in your area, but you might be able to argue that a processor failure should fall under the 8 year emissions warranty. Check your warranty information to see if the emissions warranty applies.

-Rod