Just replace the bad stock fuel pump in a 91 Honda Civic with a Walbro 190. Everything seemed good for about a week, then it died on me.
The starter would roll over but no spark and fuel.
The main relay was not clicking and no power to the ECU.
After looking at everything, I found a blown fuse and replaced it. Turn the key on and it popped again.
Unplugged the fuel pump, replaced the fuse and did not pop.
Dropped the Check all the wiring and rewired the ground wire in the tank.
Does not seem to be blowing the fuse.
However, the pump does not seem to be getting 12v. It is pumping but strong.

 

Sounds like a short (wire touching something it shouldnt). Please tell us which fuse you replaced? Also, a $15 multimeter from any local superstore will let you measure the voltage that is making it to the pump.

You can also use the MULTI-meter to (with battery disconnected) measure resistance between your fuel pump wires and Ground. Obviously the Positive should have "infinite resistance to ground" and the Negative should have almost 0 resistance to ground. Then hook up the battery again, ground the black probe to a different chassis ground...and then proceed to measure voltage on both pump wires. Again, should have about 12v on the Positive, and 0 on the Negative.

I could guess all kinds of things, but I do my best troubleshooting with a multi-meter in my hand and looking for incorrect measurements...then trace them back to find the problem.