replace water pump on a 2.7 car runs really rough on 1999 Dodge Intrepid

replace water pump would not start unless we disconnected cam sensor then it would start and plug it back in and the engine would Idol smooth give it throttle and it would start running rough around 25 then go to driving it smooth take off but around 25 starts shaking and running really bad again I'm pulling up two codes P 1684 and P 0340could someone tell me what the problem could be because this problem is driving me nuts

by in Oklahoma City, OK on March 23, 2013
1 answer
ANSWER by on March 25, 2013
possible air/fuel mix. check air intake. hoses to manifold. also test fuel pressure. try ethanol treatment in fuel to clean delivery system, and combustion chambers. rec. treatment with 1 tank premium.