T
t.mc2006
Guest
Every time it rains this thing runs terrible.It has been to the dealer a couple of times,but they cant seem to fix it either.I have already done a complete tune up-cap rotor wires and plugs with ac delco parts.I did this first.I suspected the ECM so I removed it and opened it up,sure enough you could see where water was getting in passed the seal.I dried it out in the sun and sealed it with RTV silicone and put it back in.It ran perfect for 7 weeks,even through alot of rain.2 days ago we had a storm and it rained very hard,and the problem started all over again.I do get a code 300 random multiple misfire,and a code 302 misfire on cylinder #2.Fuel pressure is normal @ 62 psi.60-66 operating,and has good spark to all cylinders.Has anyone else had this problem and were you able to correct it? I'm about to rip my hair out trying to find this problem.Does anyone know if there is a technical service bulletin on this problem??Wiring harness,ECM,???