Auto help

Hey guys, wondering if I can get some help. 1999 Avalon 115k miles, my check engine light came on about 2 weeks ago. Seems that when I stop at a light etc. my rpm drops a little, enough to make the once smooth engine rattle a little-only noticeable by small vibrations in the car which disappear if I accelerate a little, bringing up my rpm. Also, when I release the brakes on the initial take-off(without accelerating), the car barely moves-no initial acceleration-unless I press on the accelerator. In addition, I went to autozone and received the following error code:
p1135-manufacturing control fuel air metering; pedal position sensor A circuit intermittent. I also noticed my fuel economy dropping. Any suggestions would be appreciated...