It happened to me twice since I own the car (6months)
I turn on the car and start driving, then "bling" check engine light is on...usually the ecu would shut everything and drive on very rich fuel...
I didn't noticed any loss of performance, I wasn't going far so I parked the car, did my stuff...then turned on the car and drove around a bit...the light never turn on again...

then dont worry about it. but you really need to check the code to see what it was. might have a sensor coming loose

I'll have them checked next time I go to the garage! thank you!

It's a simple one you can do yourself, here is the guide

http://www.6gc.net/howto/determine_check_engine_light_codes

It's most likely 54, you probably need to top up your intercooler. Best done with the engine cold, Rev the motor a bit to activate the pump, as the water goes down top it up until full and replace the cap, the pump will turn off in 20 seconds so do it quick.

can I still verify the code if the engine light doesn't turn on? because like I said, it's random! it did it only twice in 6 months...

Yeah the ECU remembers codes while the battery is still plugged in.

To clear codes from ECU memory you disconnect the battery, or pull the ECU and EFI fuses and let it sit for 10 mins before reconnecting.

Ok thanks! I'll do this!