Contamination can cause discoloration/degradation of the power steering fluid. Did you flush-out the whole steering system after the new pump unit was installed? If you didn't, the contaminated fluid inside the steering rack mixed with the fresh fluid required to fill the new pump plus any lost during the repair. The "black" color might be symptomatic of a specific component failure but I don't know for sure.
The power steering fluid in my Contour degraded to a dark brown condition with a burn't varnish odor after ~ 3 years/36,000 miles. I did a triple flush of the system and everything has been fine now; at ~ 92,000 miles. I can only conclude that contaminated fluid was used at the factory or there was a contaminant already present in one of the parts before filling at the factory.
Dave Keller
1995 Contour SE
