Do what I've done with my VW Golf "commuter car" that always has "issues" like this.

Get an air compressor and an air gun with a soft rubber tip. Disconnect the hose to the resevoir and blow the air backwards through the system to blow out any particles. Don't go nuts and push 125psi through there - just a little at a time to push the crud out.

While the hose is off, you can flush out the resevoir...

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2001 Solar Yellow SE 4x4 V6 5spd
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Modified 2001 SE 6cyl 5spd 4x4 Solar Yellow
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