Limp Mode

I have redone the timing belts, water pump, oil, oil filter, new distributor, new spark plugs. When I start the engine its starts and idles fine but it will not rev, when I try to rev it stalls and even drops in revs.(From 1000 rpm to about 500 rpm). Could this be a bad ground connection to the engine / distributor? Or timing off by two teeth?The engoine is a 1.6 I with a mp9 fuel injection system.I also notice that the fuel level sensor is faulty as it moves up and down and beeps saying no fuel in tank.