'96 Neon Trunk Lock/Mystery Part

I've got a 1996 Dodge Neon. The trunk lock is getting harder and
harder to open. The key slides into the lock just fine but then it
will not turn either way until I get it just right. It's getting worse
and worse each day. At first I thought that it might be that I have a
worn key but the spare key (hardly ever used) does the same thing. Any
suggestions?

My second question is about a black cylendar right behind the bumper on
the front right side of the vehicle. It has two hoses going into the
top of it. What is this thing?

<jfbialek.DeleteThis@usa.net> wrote in message
news:1136407397.989025.140010@g49g2000cwa.googlegroups.com...
> I've got a 1996 Dodge Neon. The trunk lock is getting harder and
> harder to open. The key slides into the lock just fine but then it
> will not turn either way until I get it just right. It's getting worse
> and worse each day. At first I thought that it might be that I have a
> worn key but the spare key (hardly ever used) does the same thing. Any
> suggestions?
>
> My second question is about a black cylendar right behind the bumper on
> the front right side of the vehicle. It has two hoses going into the
> top of it. What is this thing?
>

Did you try to spray penetrating oil into it?