hi i left my wrx ticking over while i waited for my stepson to get his car from mot station. the cars revs went up to about 1500-1800rpm and wont drop down even after driving it 4miles home again. any ideas what to start taking off cheers j

 

you could take the idle air control valve off the manifold and clean it this sticking can cause high idle rpm.
marty.

 

just done a 36m round trip and it behaved fine so dont know what to do j