It sounds like you have a vacuum leak that is making your idle bounce, most common vacuum leak is the grommet on the breather box, this is a $3 to $4 part and requires someone with small hands to reach it, it's part #3 in the diagram.
Other issue with loss of power at part throttle is the o2 sensor, you can test this by unplugging the o2 sensor and letting it run in open loop, this will hurt your mileage a bit because it's going to run in the default ECU settings, but if the problem goes away then you know it's the o2 sensor for sure and while the o2 sensor should last, I have had one go bad in less then a year and others last 10 years or more.