VW Polo engine cut outs and gauge and steering problems

I have a 96 VW polo 1.4cl, 85314 miles on it. When I slow down to traffic lights, junctions, roundabouts it cuts out, it also cuts out when I put the clutch in to drop down gears. The speedometer and fuel gauge dont work but the rev counter and temp gauges are fine! I had a head gassket replace as well as a cable around that area (dont know what tho) my car also sounds like a tin can rattling when moving off and reversing. Occsaionally when driving at a steady speed it slows like ive drivin into a pile of sand and the suddenly picks up again. My steering wheel is at a 180 degree angle when driving straight and even tho I have my wheel balanced regularly the problem persists and when I turn a hard left or brake it sounds like a scraping noise! Please help!