Bouncing ammeter

The standard factory wiring strategy is not really appropriate for an EFI system. It makes a number of assumptions based on low power needs at starting and idle. EFI has high current demands (pump and injectors) all the time.

My suggestion is to look over your wiring and come up something you are comfortable with doing.
Find the electrical needs of the pump and injectors. These will be in Watts, or amps at some specified voltage.

There are at least two approaches that would handle the loads reasonably well.
1. Connect the alternator output directly to the battery positive.
+ use a maxi-fuse or fusible link in that line.
+ install a voltmeter to monitor the electrical system while running. One that plugs into the lighter socket could suffice termporarily.
- With this arrangement the ammeter will no longer show battery charging and disharging. it will show flow through that line when its the shortest path to something.
>A diagram of a more solid way to do this with an auxilery box and relay here. <

2. Connect all of the new loads to the alternator. A relay could be used so its powered in start and run.
+ use fuses or breakers in the connections
+ ammeter still shows charging and discharging
+ adding a voltmeter, even one in the lighter plug would be a good addition to let you monitor if the system is performing as it should.
- With this arrangement, during start power for the EFI still has long route. If the EFI needs during start are real high, say 20 amps or more, over time weak points in the original wiring may cause you problems.
- If the EFI electronics are sensitive to alternator output noise and need the battery to soak it up.
>The second and third diagrams here show ways to do this with an auxilery box and relay . <