Hard starting and running rough on 2003 Dodge Grand Caravan

V-6 3.3 ltr. engine. this started with the van almost dying with an 1/8 of a tank of fuel. we put in a full tank of fuel and a bottle of heat and a bottle of prestone cleaner. it would start but you had to put the pedal to the floor and then ease off till it smoothed out. after that it would start regular the rest of the day. finally though it just would not start, we put on a new fuel filter and spark plugs and it fired right up. put in a mid grade of BP fuel it was on 1/2 tank. ran great for about a day and half then started with the hard starting and the bucking and rough running finally it would not start at all. took to mechanic and he got it started and he took out 3 of the plugs and they were dripping with fuel and black already. it seems to be getting far too much fuel and not burning any of it. the fuel pump is good and the fuel pressure is good. the computer did not show anything but some minor vaccuum issues. is this electical??? if so do you have any suggestions? he says it will be trial and error and could be time consuming and costly. i need help

Asked by for the 2003 Dodge Grand Caravan
What codes are stored in the engine computer? It may seem like "minor vacuum issues", but it may indicate another issue.
Having similar problems as above. Sudden rough idle when gas tank was 1/4 full... 03 Dodge Grand Caravan 3.3 v6- filled tank, added a bottle of Heet. No change. Check engine light on and occasionally flashing 5 times. Diagnostic codes: P: 201, 301, 442, 455, and 456.