Since I've had my car I've noticed every now and again a slight click and a shift in my seat when first starting off. I have discovered that the seat bottom itself is a little loose and not the entire seat.

Is there a way to tighten the seat bottom so it doesn't shift and make this audible click anymore?

 

if your seat pan bolts are loose you have to remove the seat .if you are going to remove your seat you will have to unbolt the seat belt from your seat.there is a cover you will have to remove to get to the bolt.
after you remove the cover there is a inspection hole.this hole allows you to line up the seat pan rear bolts so you can remove or tighten the rear pan bolts.
to line up the bolt to the inspection hole just move you seat foward or back till you see a bolt line up to the hole then disconnect the power to the seat then remove the seat.if you dont line up the bolt you will not be able to get to the pan bolts.good luck.also remove the seat out the rear door.

 

That sounds like a huge hassle. To clarify, you are meaning bolts that secure the seat bottom to the seat frame and not the seat itself to the track?

The entire seat isn't loose, only the part you sit on.

 

before you go through the seat removal i would wiggle the seat bottom and see if there is any play in it.your problem might be a broken seat frame,had a forum member that had a broken frame that he had to have welded.

 

yes the bolts that secure the seat pan to the frame.

 

The seat bottom does tip forward and aft if I grab the front and rear with my hands. This doesn't sound promising

 

you need to remove your seat to see whats going on.