89 Dodge Caravan 2.5 turbo. Another problem appeared Sunday. As I hit a roadway with higher speeds, van wouldn't accelerate properly. Tried giving it more gas again and heard and felt a jerk, almost like a trans slip. But not the trans. It's shifting ok. Now I had acceleration before this. So what happened all of a sudden? When you take off it can accelerate to 20-25mph. Then you have to gradually wait for it to gain speed.Took for a test ride last night. Once i shifted into 3rd, I tried giving it more gas, it seems like all of a sudden something catches and i hear something kick in and I have more power. But can only do this once in 3rd. I also found a vacuum leak, will try to share pic. Not sure where it goes to or what happened to hose. Can't find anything. Don't know if this would have anything to do with it?