Steering a little bit all over the place? Vacuum pump?
 

Not sure if this just me, but sometimes it feels like the steering is a little heavier than usual and also it either pulls to the right ot the left at different speeds. Could be the roads as well, but not 100% sure and wanted to hear if this is something to get checked out?

Could it have anything to do with the Vacuum pump which seems to the the achilles heel with the 997.2?

2009 C2S 121K miles

These cars are hypersensitive to alignments. I would start there first.... find a good speed shop that does track prep as those guys "get it" and on whole, do a better job than any old shop. I am finding my 997.2 seems to go out of alignment way more than my 2000 Boxster S did... not sure why but sure appears to.

Peace
Bruce in Philly

Jack it up on one side, grab the wheel at 9 with left hand and 3 o clock with right and try to wiggle it. If there is play there is probably link/tie rods. Should be rock solid and no play. Even 1 mm play in the outside of the wheel is too much.

That will cause shaky steering.

Takes 10 minutes to check. Common on 997:s

This is good advice even if it isn't your problem. I'm on my seventh Porsche and three of them had tie rods worn. Even if the method for testing here doesn't show play there can still be issues. All three of mine I did not find until I actually had the tire rod disconnect from the hub. You'll feel a small click click on the ball joint between the inner and the steering rack.

What type of tires are you running? Some all season tires will be inconsistent.

Where are you located too, like weather conditions?

Also good advice to find a shop that can align properly.