change battery and engine ran rough under 2,000 rpm w? mil o

Just happened 2 days ago.... I just recently have my 09 Grand Caravan SXT in for recall on ignition switch and my battery started having problems starting the van with an engine boost... I was successful in moving the van to my driveway but after turning it off, it would not turn over even with engine start. After replacing the battery and when coming back from the Parts Store, my MIL came on and the engine started running extremely rough under 2,000 rpm's... I can't figure out the actual problem... I ran my OBII Reader and got an "E" after relaunching and repeating but I have no reference for an "E"...

Now, I am forced to take it back to the dealer who replaced my ignition switch of which my delayed starting problems should have been resolved but it wasn't... I just figured it was a battery going bad, but not that quickly... After taking it home, the van I put the battery on a advanced battery charger and it appeared to take a full charge but I needed engine start just to turn over the engine... after I started the van and pulled it in to my driveway. I needed to pull it up just a foot more but it wouldn't start even with using the charger's engine start... After trying to charge it again, it would not take a charge and had to replace the battery... The engine ran fine just as always and after dropping off my old battery and was halfway home, the engine started to run extremely rough but as long as I kept it above 2,000 rpm it no longer ran rough...