The first start of the day the engine will fire and idle for a few seconds before stumbling then will recovering again. This is fairly bad for the first 15 seconds. After a minute it'll be perfect for the many hours until dead cold again.
Air and coolant temps match and seem correct.
Fuel pressure is at 55psi at idle.
Injectors are not leaking.
Throttle body has been cleaned and plugs replaced as part of well over due service.

Any thoughts would be appreciated