87 turbo. Looking for ideas here. a few weeks ago, it wouldn't idle at all. I unclipped the AMM while running and it seemed to go into limp home mode and would idle. I shut off the car, reattached the AMM and it would idle again This has the 007 AMM.

So I cleaned the AMM with the CRC mass airflow sensor cleaner. and have been driving around a bit. I checked the throttle position switch and it clicks on and off whenever the linkage is moved. Car seems to idle fine but whenever I lift off the throttle after accelerating or coasting, it dies. If I lift very slowly, it will not die. Restarts every time, no problem.

Any ideas what to check? My local Volvo wrench told me the idle air motor either works or it doesn't so I haven't fooled with that at all. I have checked pretty thoroughly for vacuum leaks too.
Thanks!