2002 grand vitara 1.6 petrol.Every now and again on start up i get a noise like a fan belt slipping,at the moment as i said it is intermittent.I am going to take it to the garage but would like a bit of feed back first. I think it has a S belt i have heard that it could be the tensioner.Would you recomend changing the tensioner when the new belt is fitted or just get it checked? Or could it be somthing else (the timing belt was done 2,000mls back),i would be grateful for any advice