Why does Fuel Pump Fuse on 2004 Ford Ranger 2.3L keep blowing? The fuel pump has been replaced with a new one. The fuse blew before the replacement and after.

Check the fuel pump relay in the under-hood fuse/relay box--it may have shorted out. Sometimes, you can trouble-shoot the problem by temporarily substituting a similar pin relay in the under-hood fuse/relay box. Check your Owner's Manual for the layout of your under-hood fuse/relay box.

Typically a fuse blows for one of two reasons, a short, or excessive current draw. If the pump runs for a while and then the fuse blows, it is probably excessive draw. In other words the pump is pulling too much current (amps). If it blows immediately it is probably a short.

If it were my truck I would probably start by looking at all the connections on the pump and anywhere in the wiring harness you can trace it, for dirty connections or something funky, it could be worn wire insulation. How old is the pump? Maybe it is about to crap out and drawing too much juice. You could try taking it off, connecting it to a 12V source and measuring amps if you have access to an amp meter.

This may not be easy to figure out.