Does it start and run normally after the (shorter?) glow plug warm up interval?
Is this something that has started occurring recently, or has it always been this way?
What does the chassis manual say about it?
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 Wrangler JKU (sold @ ????) - 2016 Sunstar 26HE (sold @ 4600 miles) - 2002 Roadtrek C190P (sold @ 315,000kms)