I've read where others have had this same problem and now my S-10 is broken down until I can figure out what is causing this or where the failure/short might be located. I was going down a smooth stretch of road when the truck just quit. Towed it home and saw it had spark but no gas. Made the mistake of not troubleshooting thoroughly. Replaced the fuel filter and fuel pump before realizing that ECM-B fuse was blown. Fuel pump works fine when wired direct. Put another fuse in and it blew as soon as I turned the key on. It blows the fuse everytime the key is turned on no matter how many amps the fuse is.
1) Eliminated the possibility of a short in the fuel pump and sending unit. Still blew the fuse after disconnecting them.2) Eliminated the oil pressure switch and wires leading from the oil pressure switch to the fuel pump relay. Still blew the fuse after disconnecting them.
3) Fuse did not blow after unplugging the fuel pump relay and turning the key, so I bought a new fuel pump relay, hooked it up and the fuse still blew.4) Checked the wires leading from the fuel pump relay back to the fuel pump and they appear to be in good shape with no missing insulation.
5) Checked the wires around the injectors under the hood and they are in good shape also.6) There must be a dead short somewhere because when I hook a 12 volt test light to the ECM-B terminals and turn the key on it is bright as hell.
Anyone have any ideas? I have a Haynes, but the schematic doesn't go into enough detail on the fuel pump relay wiring. Thanks in advance to any experts who can help troubleshoot this one.