1990 200 idles fine, but has no power and stutters over 3000rpm

[David Yentema]

as the subject states, does anyone have whats going on?

I just bought this car, and after working on it for a bit I got it to start
up and idle, but it does idle a bit rough, and has a clacking coming from
the rear of the valve cover(i'm assuming it's lifter tick, just sounds
different than what my 5000 always sounded like) but when I went to put it
in gear and drive it, it falls flat on it's ass, struggles to take off, and
as it approaches 3000 it starts sputtering and bogging down. I hit a top
speed of about 45mph on level ground, but going uphill it struggles to
climb....

I've heard anything from bad air filter, to no compression. I'm thinking
it's a vac/boost leak somewhere, because my 5000 behaved similarly when I
forgot to hook the ecu vac line back up.

any ideas?

thanks!
Dave