Well, since it sounds like you may fire the parts cannon (never something I recommend) at the car, I would add the throttle position sensor as a possibility. Wish I could direct you to a diagnosis procedure, but I don't know of one.

I was having stalling issues with my '95 854T a number of years ago. No codes, ran fine etc., but just every now and then while driving, it would quit. Would restart though. Ultimately I got a TPS code. Replaced that and the issue never occurred again.

I also struggled with a MAF plug that was causing stalling. Over time, the plug just wouldn't connect tightly anymore. It looked fine, but after much research, I found that it was a more common problem than I thought. The fix was simple and cheap. All I had to do was give some tight cable-tie support to the plug connection. That problem went away too.