Before jacking the front end up today, I pulled in and out of my garage parking place repeatably, first left and then right. The sound only occurs on the left turn. Rather loud at almost full lock. It sometimes makes a lesser pop just as the turn is started too.
Once off the ground with suspension relaxed, no noise and smooth lock to lock turning. By hand, I could not feel any play in the tie rod ends nor see anything unusual.
Time for a professional to look at it.
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