My mother in law has a 1986 E350 RV (mallard). The battery went bad over winter so they bought a new one. While hooking it up her husband hooked up the wires backwards because they are both black. It will now crank just fine but wont start. Not getting spark out of coil and getting gas to the fuel rail but not though the injector I checked one of the injector wires and it seemed to be getting power, but I know some get ground through the ECM to work.
I checked all fuses and they are good. The all knowing Google says there is a fuse block under the hood but I don't see one. Any ideas?