My 2007 Audi A4 2.0T Quattro Manual has been having issues running lately. It started a while back when my cylinders were misfiring, which I fixed by changing out the spark plug coils. A few months after that, a check engine light for "Low fuel rail pressure" came on. Along with that, when I start my car, It takes too long to turn (about 7-10 seconds). When I go from a stop to first and moving, it takes more gas than usual for it to catch, and often feels like i'm going to stall it out, it also takes unusually long for the gears to fully catch. I also can barely get my car's RPM's past 4000, in any gear. My RPM's crawl up as I accelerate, and I often have to hold the gas pedal down to speed up, and it still accelerates slowly. If i'm driving up a hill on a highway, i often have to hold the gas down just to maintain speed. Does anyone have any idea's on what it could be? And how I could go about fixing it? Thanks.