Prius will start but only runs a few seconds

HELP!
My 2004 Prius is due in the shop Tues for a hybrid battery replacement. Codes indicate only one cell bad BUT...It is obviously having some problem running. We were very low on gas yesturday but wife filled it before she came home. She parked it in garage. The Hy Batt indicated all green bars.
She may not have pressed the Park button before Power - I do that a lot too.
This AM I changed the spark plugs before I tried to start it. I then started it (ICE & started-sounded OK) and backed it DOWN the driveway into the street and started down the street. The ICE stopped.
The batt indicated one blue bar so the batt would not propel it. After trying a couple times to make it run, I disconnected the 12v grd and let it sit for an hour. Then I reconnected the batt and the ICE again started showing hybrid at 4 blue bars and stopped after a few seconds. Tried it once or twice more, same thing.

What to do????? Hate to have to tow it Tues.

 

Well, I posted everything just in case.
Turns out the correct answer is -- I screwed up --
When I replaced the spark plug coil assy the right most unit connector is covered by a plastic assy - looks like a wire trough.
That is the ONE connector that must be removed. Somehow I felt that I didn't get it back on but when I looked it appeared like it was --- NOT.
what I was seeing was the body of the coil assy. So that piece of info was relevant after all.

Most 4cyl ICE would run after a fashion on only 3cyl. The Prius, however, is too smart for my own good. It know one is not connected. -- SO why does it even run the MG1 if it is so smart???

thx - I have another ?? new post