Possible, but not very likely.
A gas cap is cheap enough that perhaps you can throw one at it for the P0442.
The P0452 is an electrical fault in the pressure sensor that is mounted on the top of the fuel tank.
Personally, if you do not have mandated emissions testing, I would ignore this issue.
I just went through the hassle of trying to fix a P0442 on my 98 'tour so I could get it past emissions. In the end, I had to take it to a dealer for pressurized smoke leak testing. It finally ended up being the computer that was faulty (at least that's what they charged me for) and cost me over $700 for a system that wasn't even leaking....
Steve
