The other day, my 2009 Journey SXT AWD started shuddering. Got the code read and it was P0305, or a cyl 5 misfire. I have replaced #5 coil and all of the spark plugs, to no avail. It only does this problem when the engine is cold. This is my primary mode of transportation, so several days at the dealership (if not a week) is not really possible. I have 48,000 miles on it, and since the original owner purchased the lifetime (non-transferrable) warranty, I have no warranty left. Any ideas?

 

Only when Cold? maybe u got a leaky injector. Sometimes it leaks down while you park the vehicle, when u start it up, the cyln is flooded.
I recommend swapping out the injector with another cyln and see what happen.
And I believe cyln 5 is under intake manifold, I highly recommend you doing a Compression test while you are there. I've seen burnt exhaust valve few times on the 3.5L motor. It it shows Low compression, you need a Cylnder head.
Do it when it is Cold, because that's when u Mis.

 

suspect carbon on valves .compression test will show normal, Im not sure why#5 is worst but it is common