Help Identifying Pictures, From 74 1.8 L-Jet Engine Compartment Options

[Levi]

I'm chasing Vacuum lines and checking, fixing and replacing them, as I do I'm running across things that don't look quite right some of which I'm unable to Identify, Any help you can give is appreciated...

Can you tell me what this is, Does, it was bolted to the bottom of the Battery box. does it need to be grounded.

[Mueller]

Andy,

I took this from the Megasquirt site...gives a little info on why the resistors:

Pulse Width Modulation

Injectors are either high impedance or low impedance. High impedance injectors (usually about 12-16 ohms) can take a 12 supply directly, without a form of current control. Low impedance injectors (generally below 3 ohms) require some form of current limiting. With MegaSquirt, you can use resistors to limit current, or you can use Pulse Width Modulation (PWM), which is a software solution built in to MegaSquirt.

Levi,

It's a good idea to become familiar with these parts, helps troubleshooting down the road.

The dual relay item:
with key on, flapper opened (manually or by the vacum of the engine), this d/r gets energized, when it does, it powers the injectors (injectors fire when grounded by the ECU)

it also turns on the fuel pump...this is good to know, if having problems or testing the fuel system, you can simply turn on the ignition, and open the flapper box, now you should have fuel pressure..(as long as dual relay is working properly)