White colored O2 sensor

[mycarsucks]

Im replacing the motor on my gp and I have to swap the exhaust manifold (junkyard cut the bolts off with a grinder) and I noticed that when taking the manifold off the old engine, it has white deposits on the O2 sensor, but while taking the O2 off the junkyard engine, it has black color to it. Which one should I use in my engine? And what does this say about both engines health

 

[Schurkey]

You should use the NEW sensor that's listed as being correct for your application.

Installing a used O2 sensor is nuts.  O2 sensors get lazy with age/mileage.  They become slow.  Any sensor older than a few years or 50K miles is suspect if not outright defective.

Edited September 8 by Schurkey