Revs by itself!



I am all new to Daihatsu's and have just joined the site. I bought a Hijet (1.0L, N reg) about a month ago, and it has started to rev by itself once warm. It is fine until i've driven it for about 20 mins, then when i stop at lights or a junction, it will rev to max, then back to normal idle again. The garage i bought it from says there is nothing abnormal with it, but i think they're pulling my leg. Any advice would be apperciated.

Many Thanks,

idle speed valve

i have a ford escort as well as a 4trak and it was doing a similar thing but once i'd removed the idle speed valve and given it a clean it was ok.not sure if this is any help as the diahatsu is maybe different but maybe worth mentioning to garage if u get no other replys.
ps. tell the garage thats deffinately not normal.