Well, turned out that I did have a minor vacuum leak and one sensor malfunctioning. With those two things fixed it no longer is stalling and no more bucking at 1500 rpms. Still very hard to get into reverse. But two out of three ain't bad!

Thank you all! Very helpful info. I will definitely check for codes and vacuum leak. I checked with the Volvo mechanic I bought the car from, who is a good friend of mine, and he thought the stalling is a vacuum issue too. Too bad he lives 1000 miles away! I appreciate your help!

Hi, guys. First time poster. Looking for advise. I have a 95 850GLT non turbo, 225k, with manual transmission. A tank of a car that I have had for 12 years. I just had the original clutch replaced in a shop. I immediately started having a stalling issue. It idles fine at 900rpm when starting but whe...