Hi, I'm Greg (Indy-Tech).Welcome to JustAnswer. I'm reviewing your question now, and will post back with your reply ASAP.Rgds Greg.
Hi Kevin .
What year is your Sedona .
Need to know if you have the later model or the older system with the Fuel filter with primmer pump fitted .
Few issue will cause a hard start in the morning is as you said fuel return to tank and glow plugs .
To check do the following .
In the morning pump the primmer until hard then try and start ,if she starts a lot faster than normal
then you have a bad primmer .its letting fuel return to the tank over night .
Second on the glow plugs on the following day when the car has stood another 8 hrs .
Using a test light switch on the ignition with the test light connected to the glow plugs .
on a cold morning the test light should glow for 10 - 15 seconds ,(this depends on engine temp)
if it only comes on for a few seconds then you will need to diagnose why .
If this is the case with the glow plugs then please get back to me .
Kindest regards Greg