What voltage level when cranking the engine would indicate it's time for a battery change? Mine drops to 10.1 whilst cranking...

I don't think there's an actual cut-off voltage as such; it's more that if the engine is spinning too slowly the EMS won't inject fuel.

OK, thanks for the info...

 

Just wondered if there was a general guide line as to what level would indicate the battery might need replacing

The voltage will drop off quickly, how old is the battery. if its a 2007 original it may well now be weak anyway so could be worth considering replacement before it starts to cause real problems.

 

A good way to tell, scan the car with VCDS and see if you have any low voltage faults recorded on the various modules.

Chances are if the weather is getting warmer you could be lucky and it last you all spring and summer, but if you don't want to get caught with your strides around your sandals......