UK Car Repair: Steering problem/Wiper problem, vauxhall tigra, wheel hub

Question
Hello i have a problem with my Vauxhall Tigra 97/R reg, when i hit a speed above 50mph the steering is all over the place pulling to both the left and right, the steering is also very light. I have changed 3 out of 4 tyres and had them balanced please help. with the wipers when the key is turned once so the power is on but the engine is not running the wipers work fine but when the key is turned all the way and the engine is running the wipers have no half speed it jumps straight to speed 1 and wont turn off until the engine is turned of and the keys are taken out. The control arm and relay have been replaced the problem still happens i have been quoted £50 by vauxhall just for them to look.

Answer
Well; lets see what I can say.  The steering is clearly dangerous, is it power assist?  I would check, in order, the front wheel hub bearings, the drive shaft joints and the rack.  When you had the tyres changed did you tell the mechanic about the problem? As for the wipers, my first guess would have been the relay but clearly it wasn't. Does the key have to come out to stop the wipers? Or, do they go off when the ignition is turned off? I do not have access to a wiring diagram but have you gone on line to any chat room for your model?  Often you can benefit from the experience of others.