Audi A3 ESP fault light

Hello, I have an Audi A3 3.2 V6 Quattro Sport on an 06 Plate and it's a manual.

When starting from cold the ESP fault light comes up on the display and then goes out within in a second or so. It does not do this everyday. It has been back to the garage 3 times under warranty and there is no fault code when they have read the ecu.

One thing is that I know the car was fitted with a Haldex controller before I bought the vehicle, but has been removed. I plugged in a VAG code reader, and have found that the Haldex software is still on the ECU.

Could this be the reason? Only thing is it doesn't happen every time??

Anyone have any ideas, have read it code be a faulty sensor???