When my airpump went at 115k, it had the same issues you are reporting.

Long story short, when it did sieze up, not only did I have to replace the pump, but the fan belt had melted into all of the other pulleys as the crankshaft still pulled the belt around the non-rotating air pump pulley.

Not a fun fix!! Especially since everything reeks of burnt rubber. I had to use a little dremmel tool to clean out some of the pulleys, and a couple were so screwed I had to replace them.

I suggest checking the air pump and the air pump pulley asap.

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1995 E320 119,000 miles