Slow starting 3.0 tdi

[Mollygoogle]

As per the title. My 3.0 TDi has always been slow to turn over and start. It’s had new injectors, new glow plugs and a new fuel filter. None of those have made a difference. There are no codes. What’s next?

 

[desertstorm]

Battery?? . How old is it and is it a decent make?.
https://www.ebay.co.uk/itm/Varta-I1-Van-Battery-12V-110Ah-920CCA-Silver-Dynamic/252149062633?

 

[Mollygoogle]

Sorry, missed that off. 2 month old Bosch S4