Fuse for Mitsubishi fuel pump - 2000 Mitsubishi Galant

It is critically important for turbocharged models that the fuel pump receive the maximum amount of voltage available from the charging and wiring system. The alternator will try to maintain about 13.5 volts into the system. Resistive losses along the current path to the pump will reduce the voltage at the pump to something less than 13.5. If there are less than 12 volts at the pump, the amount of fuel flowing may be much less than expected and perhaps enough less to create lean air-fuel mixtures under heavy boost.

The instructions below show you how to bypass the resistor and relay that the turbocharged 3S models use to reduce voltage to the pump at idle. Please read through the instructions and look at the pictures before attempting this procedure. Before I did this relay/resistor bypass I measured the voltage at the pump using the method shown on my web page 2-fuelpumpvoltage.htm. At idle the pump was receiving about 6.7 to 7.0 volts. I saw from 10.6 to 10.8 volts as boost began to build and then watched that number drop to 10.2 to 10.3 volts as boost hit 15 psi or so and RPM approached redline. After performing the relay/resistor bypass I remeasured the voltage at the fuel pump with the following results.

Cold idle: 11 volts
Warm idle: ~10.6 volts
Warm idle after radiator fan kicked in: 10.35 - 10.55 volts
Acceleration and boost: ~10.5 volts