Cold weather ECU Fail ??
So she has done it again, she used to fail to power up the ECU last year when it was cold sometimes, so i replaced the ECU relay and all seemd well.
Well today the temp dropped to a shade over 5 Degress and the ECU wouln'dt power up. Ie no MIL light and EPC light stuck on.
After a while of sitting and turning the ignition on and off/waiting, the light popped on and she went straight away.
2001 A3 TQS ARY Engine. The problem is it wont happen again for a while so tracing it is impossible, grrr.