What is this plug for?

[cdmcali]

In the back left of my engine compartment on my 2000 4 cylinder 5 speed, there is 2 random plugs. One looks like it was from the factory. The other looks shady. I was curious to know if anyone else has this. This is on the passenger side near the firewall where the wires pass through.

Thanks in advance.

 

[Chuckles89]

Sorry it took me so long to go look at this...

The gray plug is for the power antenna motor in the fenderwell. I have no idea what the black one is. Did the truck ever have ABS? The ABS wires are completely different.