What is this black box?
 

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what is this black box thing that's wired into my AFM, is this supposed to be here or is it aftermarket and also I tested my AFM volts when cranking and it gets 3.9V when jumping the connections FP and B+ I still get the same reading, is this the right amount of volts?

The black box is aftermarket (do you think Toyota would use those BS "vampire" connectors?)

There are lots of wires going to the VAF. How did you "test" the "volts"?

Jumpering FP to B+ has nothing to do with the voltages you would find at the VAF.

I would remove it and test the VAF according to the FSM and go from there.

Interesting, probably some weird thing installed with promises of increased something or another. Make sure they didn’t install a turbonator in the piping:)

Get rid of it!!!

Tested the grn/yel wire which comes from the COR. Wanted to make sure there was power there. Put the red lead from the volt meter on the grn/yel wire connector that plugs into the VAF and grounded the black lead from the volt meter. I did this while turning the ignition switch to start (cranking/turning the motor over). The meter indicated 3.9 volts. Seems to me it should be closer to 12 volts? As a double check, I bypassed the COR by jumping the FP to B+ and turned the ignition switch to 'on'...not all the way to start and got the same reading, 3.9 volts. Shouldn't it be 12 volts? If not, why not? And if so, why might the reading be low?

What is the aftermarket black box for, what is it suppose to help with? Would it be better to remove it and rewire direct?

i have no idea what aftermarket "stuff" you have on your truck. (I can tell, by appearance, that the box is not factory.) If you can't figure out why it is there, then yes, you would be better off removing it. As to "rewiring direct," I have no idea how your box is wired, or into what, so I can't help you there.

Generally, you expect to find voltages close to battery or ground, and not in the middle. But you're making a strange measurement, so I wouldn't be sure what to expect. The G-Y wire connects to the FC pin of the VAF. FC is open without the engine running, so what you are measuring is battery voltage THROUGH one of the coils of the COR. What voltage you would get then depends, for instance, on the impedance of your voltmeter. I don't know why you would think there should be "power" on the FC pin.

As I've already mentioned, jumpering FP-B+ should have no effect on the whatever voltage you see at the FC pin.

A: disconnect the quick connect taps (blue)

B: never connect them again

C: push your vafm plug all the way in (its not fully seated)

D: come back if it still doesn't run.