1986 Ford Ranger 2.9 L. Is this some kind of relay?

[Danec71]

Is this some kind of relay of some sort. Can somebody tell me what it is. And what I can replace it with or does it even need to be in line at all thanks.

 

[RobbieD]

I think it's a potted diode.

 

[tw205]

It looks like the resistor uses by the ECM to monitor the spark. Engine will run without it but will throw a code 014. It is located on the negative wire of the coil