Hello all. I have a husqvarna lawn mower model HU775h with a briggs stratton engine. At first it began with idling issues so i removed the carb, cleaned it out but issue remains. I went ahead and bought a new carb and same issue. What I am noticing is that it will not idle with the air filter housing on. If I remove the air filter housing it works just fine. Any recommendations on what else it can be? Thanks