93 grand voyager hard starting

[erawtik]

Well i just bought this van and was told the water pump was bad. So i replaced it along with the thermostat, belt, plugs, wires, and new battery. When i start it cold it doesnt want to start with out a bit of help with giving it a bit of gas. Then while it is running it is a hair rough running. If i slowly give it gas idle picks up then starts to drop so i give it a bit more and same thing. Then if i let off the gas to fast it dies. If i rev it up and stop to let it go back to idle it dies. But when it warms up it quits doing this. Another thing i know this van has sat for awhile not sure exactly mabey half year to year. So i was thinking the gas may be old??? Any ideas on this problem. Oh and i checked codes and just came back 12 which i think means lost power from me changing battery and 55 which i think is end of test. Plus one other thing the spedo does not work i thought speed sensor but it wasnt coming up in codes. Any ideas with these problems?

[erawtik]

ok it is running fine now but the speedo still doesnt work. Iv checked codes and the only new code that i pulled was a 14 and from what i looked up that would be a map sensor. So i guess il pick up a map sensor tomorrow. If the speed sensor was bad could it just not show up in the codes or do i need to drive it around a bit for it to pick up on the speed sensor?