thank you all,
the suggestion to run with the heater may have helped solve the probem with my '84 240 wagon!

i ran about 20 miles with the heater on high, still had a lack of power, but not near as drastic. and the temp guage stayed level. when i turned the heater off, temp guage crawled up quickly.
BUT-
being able to drive that long allowed me to really listen and test the car up and down hills. there's an obvious vacumme leak i haden't heard before.

on top of the intake manifold, at the very top, there is a pipe, about 1/4" (6mm) diameter, with a very thick hose connected to it. this hose runs along the firewall, and down somwhere in front of the driver (left driver)

that hose has no clamp, doesn't look like it ever did, but it's sucking in alot of air at the connection to the tube.

i'm thinking a hose clamp and a thermostat are in order, and i'll go from there.

what is the tube/hose for?

thanks,
jstarr