IAC flooded?

Hi i have a tech question.When i am driving along and approaching a jnct for example sake, i slow down, move the car out of gear BUT the revs still stay at 2k. It is only when i have come to a complete stop that it then drops the revs to 1.3k usual tick over. I presume the speed sensor does this through the ECU?Now some people have said it could be water in the IAC (although a completely sealed unit through the air box i do not know how) and that ALL Exiges do this. So before i send it in for a look or not has anyone else experienced this as it only started doing about 3 weeks ago when i had it powerwashed and yes some water did go into the roof vents.Mark

I noticed this problem when playing with the idle screw on the throttle bodies.This screw operate directly on them.This means that u can let the bodies opened at idle, and this is the cause of the problem u explained.With the engine is warm the problem becomes lighter.Nicolas

If you still have the emission piping installed instead of the breather kit then its more likely the IACV has become sticky due to the gunk from the camshaft cover being feed back into the intake system.I squirt of carb cleaner in the IACV directly should clean it up.If you adjust the throttle screw then it upsets the mixture mapping, adjust at idle for 8Kg/Hr air flow to maintain the correct air/fuel ratio.