My K&N fitted as per what was provided with NO probs at all, has been on for 18months. After fitting my de-cat, Gen II + BF the car ran fine then the following week I fitted the rest of the Mongoose, car was crazy fast for about a day then ran like a complete bag of shite, wouldn't idle etc, but after a couple of days driving it was fine, so I know it's anoying but bear with it!

Loads of people have had probs with atmos DV's, I would and have just replace the standard Bosh re-circ with a DV-30.