Misfire back but on all 8 cyl (11.5 volts when missing)

[buster_cherri]

I was getting a misfire i could not fix on #5 code 0355. I istalled new ALT and battery and swap all plugs and moved all the coils from one side to the other to elimiate the coil problem. Started up drove great then once it warms up missfire. It use to only do it once in a while and if I put the AC on within minutes.
Cleaned all grounds added in two grounds cleaned after cooler pump out. Ran great for 30 min with AC on, first time I could use AC in a while. Later I drove a mile down the road no AC and miss on all 8 came back.

I Datalog and I get 13.8 Volts on my SCT when runs good and 11.5 volts when missing. I have no clue what it could be any help??????

Sometimes its great and some times it misses and then fixes itself. Charged the battery all night one mile down the road it missed again this morning. I reall dont know what else to do.

Also 3 for dealers refuse to work on it due to the KB,75 lb inj and Anderson PMS.

 

[98whitecobra]

misfire

on the misfire if you have checked all the coils for high or low resstistance the i would move on to the primary side of the ignition the reason for the misfire when warmed up or under load is that heat cause resstistance heat goes up resstistance and pull of the connectors of the injectors and test resstistance of all the injectors

 

[hotcobra03]

when you get the code for all 8 are they 351-358?

do you get any other codes with these?

 

[Jimmysidecarr]

"11.5 volts when missing"

Is going to be a bad alternator, new or not. Don't buy alternators from your local parts stores.