[schelled]

I am going to change the timing belt in my 2007 Pt, it has the 2.4 NA engine. On Rock Auto they make several distinctions between interference engines, non interference engines, water pump driven by timing belt, hydraulic tensioners, etc. How do I know what engine I have and which timing belt kit to buy? I have changed the belt on a PT before but I don't remember all these options.

 

[ImperialCrown]

Valve-to-valve interference is a possibility if the engine stops in the wrong place at the wrong time after a belt breakage. It is rare, but possible. I have never seen it happen.
There would be no valve-to-piston interference. Gates belts has a nice website listing timing belt kits and interference/non-interference engines. All PT's have t/belt driven w/pumps and hydraulic lifters.

http://www.gates.com/part_locator/index.cfm?location_id=3598&go=Interference

 

[djsamuel]

This is the one you want:

http://www.rockauto.com/catalog/moreinfo.php?pk=1330574&cc=1441915

It is the kit with the water pump (which is driven by the belt) along with the belt, idler and spring tensioner.