So my check engine light came on, nothing out of the norm for my ole beater. Well running it to ground I'm getting error codes p0201, 2, 3 and 4. But I can't find anything in the net that talks about all four at once. I check each injector 14 ohms resistance, checked all injectors conectors firing 1.9 to 2.5 various all. Most things I read said a tune up would not change it. But I did anyways. New plugs, wires, ignition coil, pcv and air filter still there. I can't see any broken wires or seperated conectors. All fuses are good. Any help would be greatly appreciated.