I had a similar set of problems. I sprayed each of my injector seals with carb cleaner. Spraying #3 resulted in a serious drop in revs. The seals are $1.70 apiece and made a big difference for my car. I just swapped them out tonight.

To do this, you will have to remove the injectors from the car. That involves undoing the fuel line (hold the line while twisting the nut) and taking off the bracket. From there, I had to cut the old seals off with a wire cutter. There is a little ridge that holds the seal in place.

While I was at it, I replaced the water temp sensor, which I knew I needed to do because the car ran ok cold, but stumbled at speed. That took a 22mm DEEP socket.