Just wanted to share some simple corrective measures that fixed what appeared to be some serious problems. I just purchased my first Volvo, a 1990 760 turbo wagon w/ 261,000, for $750. Had some brake issues & needs front struts, but what really worried me was that it wouldn't up shift unless I removed my foot from the accelerator. It would also sputter when I came off hard acceleration, sometimes almost stalling. This is what fixed it:

I adjusted the kickdown cable, which I read about in this forum. This helped a little.

I removed the mass air sensor (someone correct me if I am wrong: the part that has an electrical connector & is attached directly to the air box) & thoroughly cleaned the screens & soaked the sensor itself a few times w/ a typical cleaner from an auto parts store. In order to do this correctly I had to remove the top of the air box, the hoses, and then the two inner hex head bolts on the interior on the intake.

I changed my air filter. In doing so I discovered a mouse had built a nest @ the bottom of the air box! New filter & cleaned out air intake.

I also cleaned out the hose attached to the turbo intake, but I am sure this didn't do much, if anything.

That's it! The car runs EXTREMELY smooth now, shifts perfectly. I haven't even done the wires, plugs, cap & rotor yet.

~i