Done some work recently on an '08 XC90 w/ the 3.2L...
1) Replaced the thermostat...then water pump failed/started leaking...
2) Replaced water pump...then starter motor failed...
3) Tested starter motor by removing starter relay in fuse box & shorting the starter to see if it'd turn over...which confirmed the motor was bad...
4) Replaced the starter motor, and car started up fine.

First test drive today, got about 4 miles then cruise up to a left hand turn, and as I'm making the turn I notice I lose the power steering, and the engine has cut out. Pulled over and topped off the coolant thinking maybe it had been caused by low coolant - but no warning codes/line were showing. Drove it another 16 miles without incident. Then got back to the house, and decided to see if it threw any trouble codes - still nothing. I pop in the OBDx & the engine stalls again!

Still hasn't thrown any trouble codes! Pulled the air filter and it was dirty as crap, but don't think it would cause these very intermittent stall issues. If it was the air filter, I'd expect it to be more consistent. Think maybe this points to a short issue, like maybe shorting the starter motor relay caused some damage to another electrical component.

Any other ideas?