2002 chrysler sebring getting codes p1684, p0340, p0442, p0455 and p0456

Question

2002 sebring 2.7l engine runs fine when check engine light off then suddenly get a short duration misfire and the following codes pop up: p1684, p0340, p0442, p0455 and p0456. replaced a cracked egr hose and check engine light cleared. then I got a misfire again and the codes came back. replaced the gas cap and this did not help the situation. anyone know what could cause all of these at one time. someone suggested it may be a loose battery cable??