Yesterday car ('09 V70 w/T6) had just completed about 40 miles driving combined hwy/city. Parked for about an hour, and when I attempted to start it up, RPMs shot above 1K, then dropped immediately to around 400, and felt like it was running on two cylinders! It would not respond to throttle, or move when I put it into gear. Fortunately, is was a warm day (50 degrees F) for this time of year, so I pulled the battery post off to hopefully clear whatever gremlin had creeped into the ECU or other black boxes under the hood. I waited a half an hour, and it started up ok, so I returned the borrowed wrench and tried to go home. I started doing the same thing! I shut it down, waited a few minutes, the tried again. I was able to start it up, so tried to drive. Car went about a mile, then started acting up again. Third time starting, and was able to get home ok. After cautiously driving home, I disconnected and cleaned both battery posts and connectors, and hooked up a trickle charger overnight.After reconnecting everything today, I did a short run to the store (2 miles), and everything fine. No CEL showing now, so IDK WTF is going on here? Could it be that the corrosion on the posts/connectors was enough to make it act up? Or am I looking at some weird thing going on on the electronic throttle body/MAF?