Hello I have an audi 2.0 tdi manual 2012 and when I come to a stop I get the following alert "oil pressure too low switch off engine" when I move off it goes away. Now I had this issue looked into by an audi specialist who said that there was too much engine oil so they drained the oil and refilled it to the correct level and the issue went away now a month later it's come back. Anyone help or advise please 

Hello Akbar,

Thanks for joining and posting your issue. 
This sounds typical of inherently low oil pressure, which of course will be at its lowest at tick over once the oil has reached its operating temperature. 
If so, the following is likely to occur:- 

Car starts from cold and oil pressure light goes out and no ‘low…’ message. 
You can travel up to a few miles and no message at tick over.

Message appears at tick over after a few miles have been covered.

Message less likely to come up following an oil change.

Probably causes:-

Operating oil pressure is indeed low, and should be checked without delay, and if confirmed to be low, you have oil pump/ bearing wear issues. You must have the pressure checked only after the oil has reached operating temperature, and not just when the coolant has reached temperature - two very different situations.

Oil pressure sensor is at fault. Best to hope that this is the cause. 
Perhaps you can keep us informed as things proceed. 
Kind regards,

Gareth.