Rough idle after car wash

[mrsmith]

Hey guys, I took my car through a car wash a couple of times in the last 3 weeks. After the wash, I go home turn the car off. When I turn the car back on (no matter how long it's been after turning it off) the car RPMs barely get past 750 and then go below 500 for a couple of minutes and the idle is rough. It then snaps out of it and is completely fine. This happens maybe 2 or 3 times after every time I take it through a wash but then it never happens again until I take it through the wash again. Any thoughts on why this could be happening? Also, I just installed Stillen G3 intakes a couple of days ago and i'm not sure if they are car wash friendly