Driving home from work I realised whenever I was braking or completely stopped the n/a was still revving. When I was completely stopped In neutral handbrake on I watched the rev counter and it kept going up to 2k revs then down to 1k then back up to 2k. So I pressed the accelerator and took my foot of again and It carried on. So I pushed the accelerator up and it stopped doing it! It's Asif it was stuck or something! Is this something I need to be worried about :| ??