99 s70 keeps blowing the #4 15amp fuse in the main panel, the fuse is marked as fuel pump and ignition coil on the cover. I replaced the fuel pump figuring the pump was stuck and increasing the current to blow the fuse. No such luck, the it still blows the fuse as soon as it is inserted in the panel, the car will still not start, so I assume there is a coil pack gone bad, my question is could a bad coil pack cause this problem and if not what would cause the fuse to blow as soon as a fuse in installed, and how does one check the coil pack. Thank You

 

Could the fuel pump relay cause the fuse to blow, maybe?

 

Just because the fuse blows you can't assume a component on that circuit is causing it. While that's a possibility you could also have a short somewhere in the harness itself.

If you're going to DIY it, first thing you'll need is circuit schematic. Then start unplugging loads and/or sub-circuits on that line until you've isolated where the problem (short) is. You can buy 12v circuit breakers that would make this kind of diagnosis more practical (rather than going through a fistful of fuses).