It's alittle imbarassing to say but for the past 6 months or so when I am in a rush and feel the need to brake alittle harder than normal coming to a stop sign, when I finally stop the engine bogs to maybe 4-500 rmps. but then boosts right back up to the regular idle. it's only successfully cut off once or twice but it tries too so hard every now and then. I've tried cleaning by adding some stuff to my fuel tank. I was wondering if maybe any of you guys had a simular problem or could help me resolve this easily.