It's most likely gone into DPF cleaning mode. Need to take it out on a beat run. The computer adds more fuel to the motor to clean the DPF and it makes a lot of noise doing it. Get it up on the HWY and drive it hard. Also check your oil level.
Yep.
Maybe Old School thinking guyz & galz but ANY engine needs to be Run.. Routinely. When they sit, ALL the lubes and fluids drain down to Zip. When you do finally Start'm Up.. yul hear All Kinds of Ticks, Clicks, Whirz, buzzingz, squeaks and sing'n sounds... till everthing gets back up to Snuff... Purge, Pressure and Flex Wize.
'ol Joe
Ducky, as long as the Ticking goes away after it warms, up and driveing it for a day or so. yer good to go, IMO ?