90 Hatch w/turbo/built Z6. Just got done tuning some tonight, and did a 4th gear pull on the freeway on the way home. All of the sudden, car lost all main power. AVCR lost all power, only acc. power worked. Turned out I blew the alternator solenoid valve fuse. Replaced the blown 10A one with the 10A hazard fuse to get home.

So I searched on here and found this: https://honda-tech.com/zerothread?id=343298

That's the same exact situation. Except I've put about 2k miles on the car with the walbro, then a full night of dyno tuning, then 1 freeway pull and it blows. What makes this fuse blow? Is it a bad alternator?

 

Well, for everyone else who searches for this in the future, turns out it's very possible that when you throw a lot of HP at the Walbro, it needs the voltage to keep up.


There's a mod you can do to the fuel pump to increase voltage and flow of the pump. Run a power wire straight off the battery to a 20A relay, then wire up the relay straight to the fuel pump. Basically you bypass the stock electrical system for the fuel pump, and now it has the voltage it needs. It also increases fuel psi quite a bit.